Well, first you need to be logged in, and then you can browse to Teams which gives you a menu where you can choose between "Create a team" and "Join a team". When you choose to create your own team; you will have to fill out a Team name, Team description and a option password (a password is only needed when you want to put a password on your team when other people try to join it.). If you simply want to join another persons team, you can click on the "Join a team" link, and a search will appear, you can search in the teams with ID, name and description; and after you've looked for one..there's a "Join" button on the table. ;o)