You can't, only an admin can. You'll probably have to contact support, wait for reply, then maybe confirm some details before it all gets done. Easier to just log out and not log back in.
Basically what SS0 said above me. If you're absolutely sure, I can remove the account, but the best bet is to just not use it anymore. Once an account is deleted, it cannot be recovered, so if you change your mind down the road it's not a reversible process.
