For Cash Games, if you run out of chips or want to add more to your stack, just click on the Chip Icon with a plus sign located on the top bar of the cash table.
In addition, there are two types of tournaments that allow you to buy more chips.

• A Re-Entry allow players who get eliminated from the tournament to buy back as a new player while late registration is still open. You can re-enter as many times as you want.
• A rebuy. This allows you to purchase chips during the early blind levels of a tournament (usually the first hour) if you have lost some, or all, of your chips.
  Rebuy tournaments typically have an add-on period at the end of the rebuy period. You may add-on for the same amount of chips you started with.