Remove the magazine to your gun and safely make sure there are no rounds in the chamber. Once Cleared, safely dry fire your gun.
Use your right hand to hold the top back of the gun in between index finger and thumb. Squeeze and slightly pull the slide back. Use your left hand to pull down the slide lock on both sides of the gun. Push the slide forward so it slides off the frame.
Push forward on the recoil spring so it pops out of the slide.
Remove the barrel from the slide.