What you will need...
1 chest mount(cant be the gopro one it dose not have the holes in the bottom)
4 small zip ties or 2 big once
1 battery bank
1 gopro charger cable
1 J buckle mount
1 gopro frame
1 gopro lens cover
Add battery pack to the chest mount with the zip ties by putting them though the holes on the bottom (The sametop chest mount is the on I used) . Remember to tighten with pliers.
Put your gopro in the frame and put the lens cap on it. Them put the J buckle mount on the back of it.
Take both the chest mount and the gopro and slide the J buckle mount in the slot. Then plug in the cable in to the battery and wrap the cable around the hole thing. Now plug the cable in to the the gopro and your done.