play harder than your skill level, as if you're getting B ranks on maps, it's a good sign you don't understand it (or it's too fast/hard for you). also keep in mind osu recommended difficulty is not to be taken seriously.
if your acc is bad, download quaver or etterna and figure out your skill range so you can do judge training, where you play on a tighter judge (like playing od8 normally and switching to od8 + hr) so it feels less tight normally.
learn some patterns (you just have to know how to tap them, not know their names, their social security number, everything on their driver's license, the universe they live in down to a subatomic scale, their wife, both of their kids, you get the point.)