Deportment has to do with how you behave and present yourself. Being polite, well-dressed, and soft-spoken shows excellent deportment.
People say you shouldn't judge by appearances, but how you present yourself — your deportment — matters. How you dress, speak, look and carry yourself is all part of deportment or demeanor. If you're polite, helpful, and smile a lot, your deportment is friendly and kind. If you're constantly swearing and shouting, your deportment is negative and hostile.