In English you could just write “Self” and be fine. The urge to Latinize comes from a tradition of academics trying to make something even more academic and, historically, required the “standard” education of learning Latin (and some Greek) at substantial expense of your parents. Snooty people for hundreds of years would not consider you educated (read: part of their in-group) unless you could come up with a new university motto.

Pro Ecclesia, Pro Texana