Name your team by clicking on Team Name. Please make sure it is an original name.
Write a little introduction for your gaming team, by clicking on the pencil icon.
More information can be inputted here.
You need to check the games that your team will be competing in. If you do not check, then you will not be able to join tournaments.
Once you have completed the previous steps, just hit publish and you are all set. Have your team members find and join the team. You as team leader will need to approve in order for them to be enlisted.