Choose a game appropriate for your level of experience and your budget.  Just because you won a low limit game or two does not mean you are ready to dive into high stakes poker with pros.

Stay away from the poker table when you are emotional.  Playing reactively rather than rationally not only increases the odds that you will make poor decisions and lose money, but it also makes it easier for your opponents to study your tells and take advantage of your state of mind.

Fold more than you think you should.  There are no rules that say you must play every hand.  If you are dealt a bad hand, chances are it will not get any better once the community cards come out.

Be aware of your opponents and watch them closely, looking for clues or patterns in their behaviour.

Know the difference between playing poker alone online and playing with others in a traditional casino game.  At a live poker table your body language is on full display to your opponents.  There are also speed of play rules and proper etiquette you will be expected to follow.  This is much different than playing online poker at home.

Use bluffing as a strategic move, not as something to simply pass time or add variety to your game.

Be prepared on every bet and only raise if you think you can cover an opponent’s re-raise.

Only call a bet if you believe you can raise it if your opponents try to draw out on you.

Win with humility and lose with grace.