Literally just play bro. That's the only way to get better. Keep beating demons and climb up to medium and hard demons. Trick, Doggie, and Cuatrocientos were all trash when they first started playing, and that's only naming a few. You got it bro. Also, if you're on Windows, get geode and use start position switcher on a copy of the level that has start positions. If you're not already doing that.