Instructions
Place your belt around your waist.
Slide the end of the belt through the top of the holster loop. This will secure the holster to the belt and help hold the top part of it in place.
Fasten the thigh straps around your leg. Some holsters have Velcro straps; others use belt-type buckles. Either way, make sure that the straps or buckles are secure and snug and that they hold the bottom of the holster against your thigh so that it doesn't slide or flop around.
Place your airsoft gun in the holster and fasten the strap across the top of the gun to make sure it doesn't fall out. Practice unstrapping the gun and drawing it until you can do so fluidly.