The manager is the one that registers the team, but they can give their coaches access to edit the Roster as well. All they will need to do is add their Coach to their Roster and give them the Roster Edit access.

How to give Coach roster access:

• Log into your Customer Account.
• Select Team Name under Manage Rosters.
• Click Add to Roster and add the desired Coaches name and email address.
• For Role, select Coach from the drop down.
  • If Coach role is not an option, use the Organization's "Contact Us" option to let the Organization know you would like it added.
• Click the Add button.
• You'll then see a blue people icon display next to your Coach's name, indicating they can log in and edit the roster. 
• If you'd rather this Coach not have edit access, click the edit icon for that Coach and change Roster Edit to "No," then click Save.