Turn off Find My iPhone
Back up your iPhone
Use a trusted GPS spoofing app on a computer
Connect your iPhone to the computer with a USB cable
Open the spoofing app
Select the desired fake location on the map
Apply the location change to your iPhone
Open Maps or a location-based app to verify the new location
Reapply the spoofed location if the app resets it
Restore your real location by restarting the iPhone or disconnecting the spoofing tool