Jeez. This isn't a hard question nor some SSI stuff. He just needs to know who to talk to!

Talk to the customer service counter either inside or outside of security. You should already know "how" to sign up for a jumpseat. One caveat on int'l is you need to sign up >90 minutes in advance. And yes you're not allowed in the cockpit so really it's just non-revving OAL.