Loose fitting clothing is best. I will need access to your elbows and knees at the very least. Stretchy clothing is easiest to pull up in order to access acupuncture points along the entire body. If I need to get to a point on your back or thigh we can use draping techniques so that everyone is comfortable.
If it is easier to just bring along a t-shirt and shorts or something that is comfortable for you, bring it in and you can change in the room!