Well when I went to see her I just got stark bollock naked and lay face down on the massage table. When she came back in she giggled and said, "So you're after the sensual massage then?" to which I replied "yes please" and off we went.
I wouldn't say it was a sensual massage btw - it was a good quality proper massage that just so happened to end with an oily handjob.
I had seen her a few times just for normal massages though.
As a first timer you'll have a proper chat to start off with while she fills in some forms - I'm not entirely sure how you can turn that conversation round to "actually I'm after an oily hj..."
You could try to say you have an ache in your groin that needs massaging?