how can setup autorize myself the expense report?

My user have setup in firm limit with an cost center and amount 9999999999999999, but when I send the expense report to approve, is not approved by myself the expense report be send it to my supervisor.

My supervisor have the amount limit 99999999999999999 and then he can approve it.

but my supervisor no have user because my job is Director

please if any have some suggestions

thanks and regards

Lourdes