Poop

[Talking Poker]

#1 is pretty easy to fix. Just stop doing it.
#2 is extremely easy to do. STOP doing it.
#3 can be tricky, as it's a lot more "feel" and often times it's incorrect to fold, even though you are pretty sure you are beat.

So, work on the first two to start. Mastering preflop play (hand selection) is probably the easiest part about becoming a better player. Post-flop, especially the turn, is a lot more work.