Your best tips? I'm kind of stuck...

Making another thread for this one, since it's kind of a big one.

I just wanted to ask you experienced (and preferably successful) players if you have any tips on how i should improve my game?

'Cause I've kind of gotten stuck. I mean, I know all the basics, like positioning, etc., but I just can't stay on the plus-side on my bankroll fish mad Don't know what I'm doing wrong, should I play tighter to begin with and then bluff when they've gotten to "know" me? Should I stay long in a game or not? Maximum buy-in or not? What amount of players and strategy is best when you're trying to build up your bankroll?