Bluffing is a necessary evil in tournament poker. The need to win some pots when you don't have the cards makes bluffing a requirement to winning events. Below are a couple of types of bluffs.

The bluffs you might see can be as ordinary as an attempt to steal the blinds, to very complex schemes. You're behind or have no cards, but you want those chips. You need to get a fold.

Stealing the blinds is picking a spot to make a raise with the hope of all remaining players folding. This can be done from any position as long as you are the first to act. When you are a short stack this is usually an all in bet. As a big stack, this can raise will vary to match the situation of the remaining players stacks, and their tendencies.

The check raise bluff is based on the strength of check raising. You're in the big blind, with 78 of diamonds. You call a raise. The flop is AJ4 with no diamonds.

You check your hand and your opponent bets the pot. Now you pause for a moment, and re-raise. This bluff will usually get a fold right here. If he doesn't fold, you will fold to any other betting.

The semi-bluff is a little different. You have KQ of hearts. You call a raise from middle position from the big blind.

The flop comes J74 with two hearts. Your opponent raises the pot, representing a big hand, and discouraging drawing for the flush. This can be a good opportunity to push all in.

If he folds, this is fine. If you get called you still can win. You have at least nine outs. This is a typical semi-bluff.

Here's a different type of bluff. You are on an open ended straight draw and have called a raise on the flop and the turn. You are first to act and the only chance to win the pot is to get a fold. Your opponent has raised twice so this is tricky, he might be very strong.

Now on the river you come out with a small raise. This raise is intended to induce a fold. The small bet is to convince your opponent that you have a huge hand, and have been slow playing it. You need to believe your opponent will think this way.

There are a lot of other bluffs out there. You need to make moves like these, and others, if you want to win tournaments. You have to be able to make chips without the cards sometimes.