Imported from XRD -SIGN- Wiki, some details may be incorrect for Xrd -REVELATOR-. Please delete this message after the information below has been checked for inconsistencies.
Preface
When learning a character's neutral game you want to focus on "what's the best I can do after hitting the opponent with X move," rather than "what moves can I use to set up X combo?"
Some combos will play out just about the same with only slight variations per character, and the only thing that will change is damage based on the starter, such as a j.S combo hitting harder than a j.K combo, which hits harder than a 2K combo. It'll be easier to learn combos when you think of them as having interchangeable starters and enders, but if that's your priority you'll miss out on the focus of the game, which is the interaction between character tools that lead up to someone getting hit.
Learn combos in chunks because it's easy, but make sure to refine your understanding of when and how each move will be used in neutral, and what your best options to follow them up are.
Most new players will rush to learn some basic combos first, and with good reason since you want to get as much reward as possible off of a hit. You get a pretty significant reward for a few minutes of learning to string a few hits together into knockdown. Just don't forget that Guilty Gear combos involve an organic adaptation to your own mistakes and your opponent's bursting habits. Rote memorization of button presses will only take you so far, and sometimes the follow up possibilities for one attack are drastically different from another attack. This even applies to the same attack if it lands in a different part of the screen. Properties also change when the attack is a counter hit, you'll need to optimize for those situations as well.
Like most characters in Xrd, I-No does the majority of her damage in the corner, and with the harsh scaling on Sdive and 80% forced prorate that's introduced by attacking during RC or YRC time slow, she's only going to do her max damage if she starts combos in the corner. With the changes to the Roman Cancel system we can't confirm into HCL FRC for cheap corner push and near-max damage, so the majority of mid screen corner push options involve the 6P > 5H > IAD j.K link in order to save meter. It's still difficult even with the tweaked buffer window, but it's much easier than HCL 6FRC6, and with slight variants this string works on almost every character. Sdive knocks down now, which helps us set up oki while giving us some extra corner push in situations where we wouldn't get knockdown before. HCL ~ D also allows knockdown in situations where we wouldn't get it before, but it gives less advantage time the higher I-No is in the air, so most of the time you'd want to knock down with Dive instead.
Once you're in the corner, Pdive knockdown sacrifices a little damage, but I-No bounces out to a range where Note gets multiple hits, allowing I-No to approach safely after the opponent is already blocking. You can also use a more damaging combo ender with HCL at point blank range, which will allow grounded note to hit 3 times because of how long it's on screen before they wake up into it.
Learning in Chunks
Like in AC/+R, it's effective to think of I-No's combos as strings of a few hits that you can link together with a little bit of improvisation. Strings you'll want to be really comfortable with are:
6P > 5H > IAD j.K
j.D > delayed VCL > 5K or c.S
c.S > VCL > c.S
Airdash FFVCL > VCL / c.S or j.S
j.H > Sdive (wallbounce) > 5P or c.S
c.S > sj.S
By learning these strings you'll be able to use I-No's main combos against the majority of characters. For example, if you use a pressure string out of a hover dash and decide to mix up with j.D, the late cancel into VCL linked into 5K gives you mid screen options. Being able to link the j.D into late VCL into c.S gives you your best corner options for maximizing damage.
If you open someone up with 2K or j.S, knowing how to combo into 6P > 5H > IAD j.K will give you solid damage in the corner, and will give corner push at mid screen. This string usually transitions into a FFVCL string (so the full combo would be '6P > 5H > IAD j.K > j.S > FFVCL'). Being able to link that into j.S helps at mid screen, while linking to c.S or another VCL is optimum for the corner.
In some situations you'll be able to wallbounce from midscreen with Sdive, and you'll need to learn to catch the other player with 5P or c.S to continue the combo, usually by linking a c.S into sj.S.
Freestyle
When playing Guilty Gear, it's best to think of combos as being much more free form than in other games. Yes, there are ways to optimize your damage, but in the event that you flub your timing at a certain point in your combo, it's still possible to salvage your knockdown. For instance, if you start the combo '2K > 6P > 5H > IAD j.K > j.S > FFVCL > j.S > j.H > HCL ~ D' on Chipp, which works anywhere, but accidentally Super Jump the Instant Air Dash, that combo will now only work if Chipp reaches the corner when using HCL. No worries though! If you simply omit the j.H and cancel the j.S into HCL the combo will still knock down anywhere on the screen.
This is important in general, but is especially true with I-No. While I-No is much easier to use at a low level in Xrd than in previous versions of the game, she's still challenging and has a lot of character specific nuances to her combos. You should be willing to experiment, and you need to get comfortable with making things up as you go along. Improvisation with combos is almost a required skill with I-No, and it's part of what makes her so fun.
Going for knockdown and optimizing Oki
You get varying amounts of advantage time depending on how you knock the opponent down. Generally speaking, Dive knockdown gives a more advantageous position than HCL knockdown, which gives a more advantageous position than using HCL ~ D. If you're in the corner, Pdive bounces I-No back to about 1/2 screen distance which means her Note oki gains additional hits. More note hits scales RISC up and will boost damage on our follow up combo if our mixup is successful. It also gives more space between us and the opponent to confirm that they're blocking. If you use a note right in someone's face, they may be able to reversal through it. Knockdown with Kdive and Sdive puts I-No in a good position to use Note, 66956 FFVCL oki, or VCL YRC oki.
If you get the opponent to block a distant note after Pdive knockdown, you can take a gamble on 66956 pressure. Use that technique to airdash in their face while they're forced to block a note and run a block string. You'll want to learn a variety of block strings to further vary your mix up, but a general string is 'j.K > j.S > j.K > j.P'. This string will continue to build RISC while the opponent is blocking, and it ends with a mix up option. Land into 2K for a low (or feint/2P into throw), chain j.P into j.D for an overhead, or do a slightly delayed VCL and YRC to frame trap. I-No's j.P is a level 1 attack, so it has 10 frames of hit stun, and VCL has 11 frames of start up, which leaves a small gap. Do the VCL slightly late to make it easier to get YRC instead of RC, but this is a frame trap option. 2K is the safest (frame tight if they don't instant block) and does the least damage, j.D hits harder but leaves a gap that they can attack through, and VCL YRC will bait a punish for j.D with the time slow and lead into the most damage (also allows another mixup if they don't take the bait). Of course, if any of these are successful you're doing damage with increased RISC, so it'll do 20-40 points more damage than normal. This is a major benefit to Pdive oki with distant note. Make sure you learn to bait Dead Angles, and make sure to use other block strings so they wont IB and punish every time. You can even sneak a ground throw in if you're clever!
Chemical Love Derivative (HCL ~ D) allows us to knock down in many more situations than before, but it offers the least time to set up oki. It seems that we get more time the closer we are to the ground when using it. If you have no alternative method for knock down, or have meter to burn and want to push for max damage, this is what you'll wind up using. Oki after HCL ~ D is actually pretty good if you have meter to spend, so don't avoid using it. However, be aware that you shouldn't use ~ D at all times just because it's "free damage", especially if you can knock down with HCL by itself. There's a point where the extra damage isn't worth the lost options for oki. In those situations, if "giving them the D" doesn't finish them, keep it in your pants.
Sacrificing a significant amount of damage for slightly better oki is probably a bad idea, but all things are relative. Damage now is better than damage later, but 3 extra points of damage isn't worth oki that gives the other player an escape route. Also, play to your skill level. Some of the mid screen combos that involve Sdive relaunch do as much damage as their HCL ~ D counterparts, but give better oki. If you can't consistently pull them off, you're better off going for the sure thing. In some cases you can end in knockdown after HCL without using ~ D, but if you're ending the combo after only a few hits the extra damage might be worth it considering the knock down is occurring near the ground instead of in the air.
Combo Optimization
The "best" combos are subjective. Some give the most damage, some give more meter gain, some give better oki, and some may even remove a very difficult link at only a minor expense compared to the more optimized version. Even with experimentation among an entire community of I-No players, we're not going to find every combination of attacks that's worth doing. Spending some time on Research and Development is part of developing as a player and having fun with the game. If you want to optimize combos toward a specific end, here are some tips:
1. Higher level attacks scale better than lower level attacks. That means that 5H is going to scale the damage of following hits less than 5P does, and that's cool because 5H does more damage too. As far as I-No goes, if you can find a way to make stuff like 'c.S > 5H > j.H > Pdive' work in place of 'c.S > j.S > j.H > Pdive' you can squeeze a little more damage out of your combo, not just because the 5H hits harder than j.S, but also because it scales the rest of the combo a little better. Unlike some games, doing 4 jabs into super is not optimized damage! You'll do less damage that way than if you hit with the super raw.
2. Hitting with higher damage attacks earlier in the combo is better for damage output. Starting a combo with VCL loop (c.S > VCL > c.S > repeat) will result in more damage than leading into it after a Pdive loop. In order of damage, Fortissimo (air Overdrive), the second hit of 6H, VCL, j.D, and 5H are what you want to try to use as early as possible in combos for damage optimization (j.D applies an 80% prorate if it's the first hit in the combo, so use it after HCL/VCL YRC). Comboing into Overdrives later in a combo is still effective as they seal the opponent's Burst, but if you want to do as much damage as possible you want to hit with them early.
3. Sometimes it's worth it to use a worse move early on if it means you get a better follow up. In some instances you can get 4 reps of VCL loop, but you almost always have to combo into 5P at that point, which might leave you pushed out too far to hit with Pdive when you follow up with 'c.S > sj.S > sj.H'. You might do the same damage, give or take a point, with the 4 rep VCL loop without having to do as many hits, but ending the VCL loop early and doing a Pdive loop may leave you with Pdive oki.
4. Different moves give different amounts of meter. In I-No's case, Sultry Performance (Dive) gives more meter than Chemical Love. Hdive is great for building meter as it hits 3 times, but it also does very low damage. Leading into a VCL loop early and ending with a Dive loop is generally really effective when trying to optimize combos for damage and meter gain.
5. In Xrd, you need to be cognizant of how much health the opponent has remaining when you end and confirm your combos. Guts kicks in when the opponent reaches 50% health remaining and reduces the damage they take. For this reason, an easier combo that doesn't attempt to fully optimize damage output might actually do the same or slightly more damage than a harder combo that tries to squeeze in every trick you can. An example would be starting a combo with Fortissimo in the corner against Chipp. Following up with c.S > VCL is the standard option, but you can squeeze in more damage with j.D or 5H. Except that Chipp's guts will kick in early and the combo will actually do less damage due to VCL being scaled really hard earlier than expected.
Tips for Difficult Combo Strings
When first learning the '6P > 5H > IAD j.K' link, make sure to follow up j.K with j.S. There are multiple ways to screw up this tight link. If j.S comes out instead of j.K, you're doing j.K too early. If j.K comes out but they tech, either the j.K was too late, or the IAD leading up to the j.K was too late. If you flub the IAD and wind up jumping in place, you're probably doing the input too fast or too early. Take your time and work at it if you're having trouble, as you most likely need to slow down until you can do the input consistently, then speed up until the combo stops dropping. Just feel it out.
Here is a thread on Execution Tips