1. Have your audio files ready to Upload. New songs make it into the Activity Stream once. This is a very popular place for members to look for new songs. Make sure yours has an audio file.
2. Have an image ready. A collaboration with no picture gets little attention.
3. Give some thought to the license that suits you. You will be asked to select All Rights Reserved or a Creative Commons license. Here is some information on Creative Commons license. You can change the license at any time with the approval of other collaborators.