The most important thing to remember when trying to be a successful poker player is to stay within your bankroll limits. It doesn’t matter if you play $2-$4 Limit or $100-$200 No Limit, if you don’t have the funds to enter the game, you can’t win.
Poker has great variance, and your bankroll must be able to sustain a prolonged streak of losing. Even the best players will have bad runs lasting months, and in some cases years. When you make a big score in a tournament or have a good night in a cash game, keep that money aside and save it for when you need it. Don’t go out and blow it all at the blackjack or craps tables. If you must play other table games, then have a separate bankroll for that, but don’t use your poker money for anything but poker.
The beauty of playing online poker is how quickly you can win money compared to sitting in a home game or at the casino. You see probably 3-4 times as many hands online as you would playing live, so on a good night you might make a ton of money. The flip side, of course, is you might lose your whole roll in one night, and trust me those are bad times. Truly successful players, and by that I mean people who are playing poker to make money (as opposed to those just there for the social aspect of the game) will put their winnings in their bankroll and not take it elsewhere. Obviously at some point you’ll want to take some out to pay bills or whatever you are playing for, but the key is to keep your bankroll at a nice, consistent number.
It is much easier to play poker if you have the comfort of knowing that one losing session is not going to cost you your whole bankroll. You have to look at it like a long-term investment. In order to be a winning player, you have to feel comfortable at the table. The easiest way to do that is to know that you can afford to lose, and a well-managed bankroll can give you that.