Experimental Build 188.8.131.52+
Using the thumbstick on oculus or vive tracker, navigate to "Wearables". Then press the "trigger" to select it. You should then see clothing options. Selecting them will toggle the clothes on and off.
As of Experimental Build 184.108.40.206, there is a limited set of clothing of that is available to each character. More will be added over time.