I own an LG Keybo cell phone; I am rough on my kit, so I purchased the clear plastc case to keep the phone protected. Once I cracked the case, it was a "Duct Tape Man" call.
You will need Duct tape, scissors and a plastic cell phone cover. The cover is removeable, so when you are out and about you can un-armour your phone and look normal.
I think this is the shortest instructable ever; cut thin strips of tape and apply them to the plastic case; I used a sharp knife to cut holes for the camera aperture, the front screen and the speaker.
Before putting the cover back on the phone, I suggest a piece of clear plastic screensaver
on the screen. Tape up the rear cover as well, and then voila: an ACU digital camo stealth communicator.