Aaron "GambleAB" Bartley
One of the most important poker lessons has nothing to do with how to play Aces in late position or how to adjust for the maniac in seat three. It's how to manage your money in a way that will make it grow as quickly as possible with minimal risk.
Some of the most highly skilled players in the game have gone broke (repeatedly) simply because they played too high, too fast, too often. How can we make sure this problem never happens to us? It isn't a matter of smarts, but rather, one of discipline.
The most important step is to be honest with yourself. You should know your relative skill level at all times. Suppose you're a $1/$2 No-Limit Hold 'em player who's had a great night, and you're toying with taking a shot at the $5/$10 game. Your bankroll is up to $1,500, but you would need to bring at least $500 to the table in order to play comfortably at the higher level.
Why would you risk putting a third of your bankroll on the table to play in the $5/$10 game? For starters, your bankroll isn't big enough for the stake; more importantly, you also need to consider that the skill level of the $5/$10 players is greater than the competition you're used to. (That's not always true, of course. There are some very skilled $1/$2 players and some weak $5/$10 players, but it's not unreasonable to assume that the higher-level games are filled with better players.)
This is where self-control comes in. One slip-up can spell disaster for a bankroll, and watching six months of hard work disappear in six hours of foolish play is enough to crush anyone's spirits.
The safest course of action is to continue doing what you're doing. You're beating the $1/$2 game for a tidy profit every week - stay right where you are. Continue proving that you can beat the game. While you're doing that, your bankroll should grow accordingly. Beating a game for six days is proof of very little. Beating the same game for six months is better evidence that you are a winning player.
Start tracking your results. You can buy tracking software or easily create a database of your own. Put in all of your information after each time you play - limits, time at the tables, profits/losses. Go over your information every few weeks, both for your recent play and for your entire poker lifetime. Try to spot bad trends before they get out of hand. If you've been playing well at a certain level over a long period of time, only then should you consider moving up to the next highest level.
Above all, know where your money is at all times and how it is being used. Ask yourself, "Is this too much risk for me considering my current bankroll?" If the answer is yes, do the responsible thing and change tables. Months later, you'll be thankful you did.