Open Clash of Clans
Tap the Settings icon
Tap More Settings
Tap Change Name
Enter your new name
Confirm the change
Use your free name change if available
Use Name Change Gems if you have already used the free change
Open Clash of Clans
Tap the Settings icon
Tap More Settings
Tap Change Name
Enter your new name
Confirm the change
Use your free name change if available
Use Name Change Gems if you have already used the free change