Your username is the one you gave when you authorized TAD. Usually, your Discord username. We use the free Discord community system to preserve anonymity of TAD users.

Why is anonymity important?
In creative fields, the aura around personalities can often come in the way of the work done by those personalities. This can be both a privacy issue as well as an issue of credibility. Architecture works need to be understood not because of the person who designed/made it but because what it really and truly is. By itself.

Feeling lost? Start here or Start learning TAD using tutorials.