Tip One: Mix Up Your Play: Once you have mastered the fundamentals of a particular game (for the purpose of this article we'll use No Limit Texas Hold'em) it's very easy to lapse into predictable play. This is particularly true when playing online. While live casinos are literally designed to keep people involved and stimulated, your home or office most likely has the opposite effect-which can lead to just "playing by the book." If you find yourself playing robotically: failing to adjust your play to the table, failing to notice the tendencies of each player, making moves without asking yourself "what am I trying to accomplish?", then it may be time to tweak your game a bit. Instead of waiting for Queens, Kings or Aces, raise with a 7/2! Not only will it help get you out of your funk, but it'll also keep your opponents off balance.
Tip Two: Online tells: The most reliable tells in online poker revolve around betting speed. The easiest ones to pick up are the "dramatic pause" tells. A long pause followed by a bet usually means the player is strong and wants you to think he is weak. A long pause followed by a check usually indicates a weak hand. This player either wants you to check so he can get a free card, or wants you to think he has a strong enough hand to "think" about betting. You'll rarely be check-raised by anyone who took a long time to check, it's not a normal betting pattern. When check-raising most players want everything to look as normal as possible to help make sure you'll put in a bet before they spring the trap. If you do get a check-raise from a player who paused heavily before the original check, be very careful. You should also watch for instantaneous bets and raises on the turn and river. This usually indicates a powerhouse hand and an attempt to get you to call by intimidating you into it.
Tip Three: Limpin' Ain't Easy: Although this applies to both live and online play, we see it so often in online poker games that it had to be included: don't limp when you're the first to enter a pot! The logic behind this tip us that since you have no money involved in the pot, if you fold you lose nothing. Therefore, if you're going call you had better have a hand that expects to earn money-and if your hand is a favorite, you should raise. In addition, you will also stop giving away valuable information about the hands you are playing (astute players will quickly divide your holdings into raising and calling hands). By raising every time you enter a pot, you reveal the minimum amount of information possible. (It should also be noted that in Hold'em there a number of hands that are not worth a call, but are worth a raise-however, that's another article.) In short, the best way to think about this rule is that if a hand is not strong enough to raise with, it is not strong enough to call with.
Of course, in poker, there is an exception to every rule. If for instance, you're holding Aces and you know that the maniac to your left will raise if you limp in, then by all means, limp away. However, this play is a much more advanced move and you had better know what you're doing before you try it. Not only do you risk wasting a big pocket pair, but you may easily end up going broke if your opponent limps behind you and makes two pair on the flop with a K,5.
Tip Four: Short-Handed Play: Most likely, a good number of the tournaments you'll be playing online will be Sit-and-Go's (9-handed games that begin as soon as 9 players signup to play.) When playing Sit-and-Go's you'll inevitably be faced with short-handed play (or at least you hope you will be). When playing short-handed, aggression is key. I'm sure you've seen it before: the game gets down to three or four players and suddenly the guy on your right is going nuts! He's raising, re-raising, and completely dominating the game. To the beginner, or to those inexperienced in short-handed play, this wild-man appears to have just thrown caution to the wind. He finally shows down a hand and he's holding K,9! However, he probably won the hand-and he probably stole a bunch o' blinds before that. So what's his trick? Aggression. A complete poker player must learn to play a solid aggressive game. It's simply not enough to sit back and wait for good cards during 9/10 handed play, only to fall apart when you're close to the big money spots. For example, have you seen T.J. Cloutier at a final table? He's about as tight as they come until he reaches short-handed play. That's when he comes out firing. He does this because he knows that if he doesn't, someone will-and then it'll be him getting run over and not the other way around.
I know this tip may make you a little uncomfortable if you're generally a tight player-but believe me, once you learn to enjoy short-handed play it's probably the most fun you'll have a poker table.

Bio: Nick Standlea is an owner of Hold'em Shirts & Gear and Hold'em Shirts & Gear (CafePress). For additional poker articles visit Hold'em Shirts & Gear's article library.