You take a picture of your character ingame, or get someone to take one for you.
You could get a friend or just someone in general to take a picture of you infront of a greenscreen to make it easy for you then edit the picture in whatever way you want while still following the rules.
All i'm saying is, this would just make it harder for crim as you now have too look for certain things to make sure you arent killing a unarmed civ newplayer around a raid