As detailed at length in the betting tutorial you should always make sure you have a reason to bet. The main ones are:
- For value - To increase the amount you win when you have the best hand.
- For protection - To protecting your hand from opponents' dangerous draws.
- To bluff - When you think the only way you can win the hand is to bluff and you are sure your opponent will fold.
- For information - To see how your opponent will react.