1. Pull out your mobile spawn.
2. Find any rock/boulder that is as high or higher than a soldier that is crouched.
3. Move slowly across the entire rock/boulder while placing your mobile spawn in each possible spot.
4. Make sure you cover the entire area and be patient.
5. Eventually your mobile spawn will fall through the rock, and land on the ground below it. At this point, you must die, then spawn on your mobile spawn point. Now you may do whatever you wish.
Credit goes to M4V3R1CK72 for this.