Armed assualt and armed assualt demo custme faces

How do you install these? my firend did it a while back but has been on since.

im palying the demo for the game its self and ive seen a few custme faces and now i want to have a few
anyone know how to install them?

From what i remember, you have to pack them to a certain filetype (.pak or .pki, i dont remember exactly). All released mods you find online are already in these files. You just put them in the Addons directory in your arma install dir. Im not sure if all of this is correct, but you could always ask your best friend Google.