every 24hours. Half of the content rewards goes to the author. Once you are paid, half of it is in SteemPower, which allow you to earn more by curating. (Can also be withdrawn through 104 weekly payments). The other half is Steemdollars. You can exchange SteemDollars for Steem and then exchange that for bitcoin via blocktrades.us
RE: When do you get a Steem payout for posting?