As an Admin logged into the back-end of Luminate:

In order to change a Participants team (or create a new one) you will need do the following:
  1. Go to Fundraising -> Teamraiser
  2. Find the Teamraiser and click Manage
  3. Find the Participant
  4. Edit the Participant
  5. Click the blue link that says "Change Team Membership"
  6. You can then add them to an existing team.
  7. If the User wants to create a new team:
  8. In the upper right, click the link that says Make the participant the captain of a new team