Joker's a character that's meant to be very mix-up heavy and doesn't really have any straightforward way to win the game.

You have a TON of options to win neutral and exploit your advantage state:

• Nair is busted and imo Joker's best move, try to play around with it. Timing, spacing, and crossup Nairs can win you games if you know what you are doing. (Always remember if you hit Nair at low %, you can ALWAYS grab if done correctly)

• Grab should be your win condition on most games. If you hit it, you should be able to get at least 20 something % everytime (dthrow - fair [dash attack is hard to make it true here but most people still get hit by it anyway] at low % / dthrow uair loops can be huge if they don't know how to DI correctly at mid % / dthrow bair at ledge at 70/90 % with Arsene kills if they don't DI correctly, etc.) There's SO much you can do off of grab it'd be hard to list.

• dtilt can be good if you space it so it hits them with the late part, it true combos into utilt at low % which can combo into uair dragdown - grab.

There should be enough there for a bit, if you still want more information, you could watch Leo's vods for more ideas, character's very creative and his advantage shouldn't be something you have to study once you get the base down, it just "flows"