When I'm learning a new character, I usually have a process that I go through before I fight against another person:
1. Learn what every single one of your character's moves do, know the properties behind each move and what they can cancel/gatling into (Counter Hit, Frame +/-, other random effects such as vacuum or invulnerability).
2. Learn the BnB combos, what good is it to hit your opponent if you don't know the follow-up for the move that landed?
3. Learn block strings, SAFE block strings. 5D into Sledge B is anything but safe.
4. Learn how to tick throw and what moves to tick throw, this is pretty damn simple. Tick throws are incredibly important if you're playing as Tager.
5. Learn to hit-confirm, there's no point in hitting your opponent if you're going auto-pilot and continuing your block string even after the hit has landed.
6. Learn gimmicks, but don't be predictable when using them. Vary your gimmicks accordingly.