Secondary Weapon Mounts Help

I've been looking but have had a problem finding any tutorials on how to do secondary weapon mounts. I'm working on some of Sean Bradley's ODST armor and would like to have a pistol for my secondary weapon. I know I will want to put either rare earth magnets or a piece of metal in the thigh plates, but any suggestions after that?

I'm thinking I will need a type of clip to keep the pistol secured on my leg. What kind of clip would I need? How would I strap it and where?

Any help would be greatly appreciated.