Whether the characters you're designing are made to be played by the gamer or whether they're NPCs, take a look at:
The way they walk and run
Their fighting moves
Other ways they move
Their idles[1]
[1] An idle is the movement or movements performed by a character you play when you've stopped moving the character about. Idles are used so that the character doesn't seem stiff and lacking life. In some games, funny idles are occasionally used to provide humor.
Other animations they might have
Their taunts
Their face
Their clothing
Their weapons
Their tattoos or other body markings
Their dwelling, if they have one
How many of these forms of non-verbal communication can you use to express traits on the character's Diamond?