Turn on your Xbox 360
Go to Settings
Select System
Select Storage
Select All Devices
Select Profiles
Highlight the profile you want to delete
Select Delete
Choose Delete Profile Only or Delete Profile and Items
Confirm the deletion
Turn on your Xbox 360
Go to Settings
Select System
Select Storage
Select All Devices
Select Profiles
Highlight the profile you want to delete
Select Delete
Choose Delete Profile Only or Delete Profile and Items
Confirm the deletion