First, log in to www.groupvalet.com (this cannot be done in our app) and in the middle of the page click the My Groups tab. Find your group and click on the "Go to Group Homepage" button. Once there, on the left side click the "Manage" tab and the click "Edit Member". Choose the member you want to edit and follow the steps.
If you change the member's email address, you are changing it throughout GroupValet for them. They will need to use that new email to log in from then on.
If you do not see "Edit Member", that means your club has turned this feature off and you'll need to have the member update their own information in their GroupValet Profile, which is in the upper right after logging in to www.groupvalet.com.