General Tactics
Potemkin relies heavily on reading the opponent, patience, and understanding opportunity, often moreso than any other character. I highly recommend understanding that just because a grappler is easy to play at a basic level doesn't mean it translates well into high level. As you progress playing Potemkin, you will need to cut bad habits because single opporutnities are what enable you to win a game.
At a glance: Potemkin is slow, has predictable and sometimes costly mobility, but has a powerful up close game once he gains momentum. He is also monsterously powerful in the corner with strong confirms into ~50% damage off mostly any move and relevant meter. When playing against long range characters you'll need to leverage what limited tools you have. Here's a quick rundown on what's available and when to use it:
Whiff punishing - The act of attacking a person who just whiffed a move. You don't necessarily have to hit them, you just need enough time to put them into block stun to turn this into a marginal advantage. You can sometimes use slidheade or hammerfall to do this, but more likely you will be using 5H, 2S, 2K or 2D. You may use other moves, but these are your key attacks. When using a special cancelable move, be sure to cancel it into hammerfall -> break, or slidehead to get a better position afterwards. Do the most powerful knockdown combo in your disposal assuming the opportunity arises instead.
Patient movement - Walking and jumping, using hammerfall -> break, or double jumping in slowly. Don't be predictable with how you avoid projectiles, or simply rush in doing this. Take your time and see what buttons the other person presses. Making sure your approach is varied in both timing and method will mean the opponent can't always have the perfect counter ready.
Hammerfall break/yrc - A different category for a different reason. You can YRC as sort of a ghetto dash and get frame advantage after the freeze to choose your mixup afterward. This is more of a hard long/mid range counter. hammerfall has a pretty obvious startup and can be countered on reaction easily, so be careful. Try to use it to beat single strike moves with few cancelable properties.
FDB - Good for fireballs, basically. Just walk forward or jump in afterward.
Raw Slidehead - Possible to punish, but harder. Usually this means the opponent has to keep their mind on this along with oher things, and if they expect a slidehead, you can use that moment to sneak in forward a little further, in case they have a direct counter to that method planned. It's also good when people land because it's a predictable timing and when someone is high in the air, they will be less able to see the startup of this move.
Mid range
Potemkin has some ok mid range stuff. His S buttons (all of them) tend to be his best attacks here. 2K, 2D 5S and jumping in directly, along with Megafist, Hammerfall (see above for reasons to use it), and simply waiting are all good options. Fighting a good mid range character like Sol (closer in) or Ky (farther out) can be an excersize in frustration and you may have better luck fighting them from outside their ideal ranges and moving in quickly. If a character has weak mid range, Potemkin tends to do okay, just look for an opportunity to get in or knock down as best you can, or Hammerfall YRC for a free ticket in. Jumping is also good if they're not expecting it. Potemkin's tools here tend to vary the most from matchup to matchup.
Close range
Where potemkin shines. What he doesn't have in speed, he has in power and psychology. Remember that while Potemkin has a command throw, and is a grappler, this doesn't mean you should focus on throws. Throwing is for people who are already trained to block. Think of your opponent as puppy, and you're teaching him not to be bad. If you don't teach him to sit first, how else are you going to throw him into the stratosp-okay bad example. Anyway, if you need to make sure a person isn't jumping or backdashing, use basic strings staring off your weaker moves, then doing Hammerfall break or hammerfall YRC to get in again. Keep this up until you think "this dude is just gonna block all day", then you Potemkin buster. The best part of playing Potemkin is at this range, you're playing RPS and all of your options do a ton of damage, and you have more information to work with. If someone keeps getting hit by basic attacks into 2D, don't stop doing it! Odds are they're trying to do something silly like jump or backdash or mash. If it works, it works, don't feel bad about doing a basic string over and over.
If someone is jumping away (and only jumping away), and you don't have enough time to do a basic move by the time you reach them, you can use Heat Knuckle to punish as a guess.
If someone jumps away, you can also do things like j.P repeat until you land.
Dealing with stuff
If someone is jumping at you, your best anti-airs are 6P, Heavenly Potemkin Buster, or jump as they come at you and air throw.
If someone is running away a lot, LET THEM. Just walk towards the corner and punish their escape. To punish getting out of the corner, look above since most of the time they'll have to jump. You can sometimes 2HS if they're at a weird angle. j.P a lot works too topush them back in the corner. Once in the corner, you have access to 6K and Giganter combos which do a lot of damage.
If you're stuck blocking, just Instant Block and wait it out. Sometimes there's situations in which you can do something weird, but most of the time you'll just have to eat blocking for a while. learning to IB will give you a lot of meter which you can then use to kill a person quickly, or to faultless defense if you're in real bad shape.
If someone is poking at you from mid range, ry and move backwards and then move forwards. usually people think "potemkin will move forward", so they'll adjust their spacing around this. IF you move backwards, you can often change around the ranges of moves and find a whiff punish, or a new place to jump, or force them to run in etc which can give you new and different opportunities.
If someone is anti-airing you a lot, first think: "is it because i jump a lot, or predictably after certain moves, strings, etc?" if so, try and stop and move in instead, when people look to anti-air you, most of the time, they'll look up for a half second when the look for the jump. They will be less likely to pay attention to other opportunities. The other thing to do is j.D, or double jump j.D, often times this will make someone's 6P whiff.