No limit hold'em means you can bet whatever amount you want when you want during a hand. But nevertheless dont just bet randomly!
The very best players bet consistently throughout a hand.
Espscially in tournaments it is important to size your bets based on the size of the pot and the size of your stack.
The "ideal bet":
-between 1/2 and 2/3 of the pot.
-consistency: pick a percentage to use throughout the game or tournament no matter what size the pot is.
The opposite of the "ideal bet" is the "minimum bet". It is equal to the size of the big blind.
A "min bet" is almost never correct, unless the "min bet" is equal to 1/2 or 2/3 of the pot.
The "pot size" bet:
-A bet equal to the amount of chips already in the pot.
A "pot size" bet is typically not correct, but it can be used in certain situations.
-Puts maximum pressure on an opponent without betting all your chips
-To confuse opponents if you hit a great flop
The "all-in" bet:
-A bet with all your chips.
Allows you to apply maximum pressure on your opponent. Its the right play to make if you are betting 1/3 or more of your entire stack. By moving all in instead of betting 1/3 of your stack you have no further action in the hand, but to sit back and watch the cards. And you dont have to make a desicion for the few chips you have left.
If you have less than 15 times the big blind pre-flop, moving all-in on any hand you choose to play is the standard move.