You go to your wallet by clicking on your profile picture and selecting it in the dropdown.
You then find the steem, I believe the first thing there, and click the arrow.
It should have a button to send it, and then it's straightforward.
Remember to go to the server and let the bots know first though, and you may need a donation if you haven't been on here for a week for a little steem...unless you have some crypto to trade in.