Have a look at various 'SM for beginners' books: there's one called something like 'The Sexually Dominant Woman: A Workbook for Nervous Beginners'.
Some women are open about being, well, women. Others are convinced you have to pretend to not ever have to pee, poo or have periods. I've had partners use a diaphragm for mess avoidance, and yes, I can tell it's there. You could say it's part of your contraception, but apparently some clients don't like to think you're ever fertile as well.
As far as making noise is concerned, I can't fake it remotely convincingly. I also have visible evidence of one sort of arousal... or its absence. So I make 'not faking but guiding' a feature. Works better for regular clients too - do you want someone convinced that X makes you really horny, baby, and so doing it again and again when it actually doesn't do anything for you at all or, worse, is an active turn off?