It is always imperative that the objects he uses intimately distinguish each person. Often the attire distinguishes people. Else, it is the wallet, pen or a bag that distinguishes him. Cartoonists have an eye to pick the most distinguishing and visible character of a person. Then they will tag him with it. If tangible elements are lacking in a personality, then intangible elements are looked into : like the slang he uses or the twist in his language.
In a trek, guess what am I tagged with?