You can choose your own avatar at any time while visiting Outerworlds. Most worlds have both male and female avatars available to choose from. Some worlds even have non-human avatars available.
Avatars often move in a lifelike manner as they walk around Outerworlds, or even when they are standing in place. Avatars also typically have one or several gestures they can perform. For example, if you are having trouble getting someone's attention, try waving!