Show up 5-10 minutes before your session starts. Bring mouthwash with you. Walk in the front door. She'll ask if you have an appointment. You will say you do, and name the girl. She'll ask for the fee, usually $150 for 40 minutes, if that's what you booked. She'll ask you if you'd like some water, and she'll probably ask you to sit for a minute in the waiting room. Shortly, she'll bring you to your room.
Shower. Use your mouth wash. You got water at the front, so that helps. There is soap there. Scrub, especially between your legs - don't want any unpleasant odours down there. Finish up, dry yourself, wrap in the towel, and sit on the table. Soon you'll hear the click of heels coming down the corridor, a knock on the door, a "hello..."
The rest? Depends on you and her. Don't believe everything you read here in reviews. There is a tremendous amount of difference in what Girl A does with Boy B, and what Girl A will do with you, and what Girl B will do with you or anybody else. So don't go in expecting anything extra. Your appointment, officially, is an exotic massage - you'll both be naked and she'll rub you, and you can rub her, breast play. You'll get a happy ending. The kissing, cuddling, licking, fingering, and extras are at the descretion of the attendant. But she is there to please. And the BJ and FS options, they are offered by some but not all, and you should expect to pay extra if that's what you want.
Post-session shower... she might join you if you're lucky; chances are she'll send you in first. Clean up, tip if required or if you want to, and she'll probably walk you out to the front.