Will she do it in free chat?
Sometimes, and it usually depends on the room. Free chat is where she warms up and where the tip menu runs, and a lot of these women will go a long way there if the room is paying attention. Anything specific is what private is for.
How do I ask for something in particular?
Type it in the chat box under her stream. She reads it live and she will tell you whether it is a free chat thing or a private thing. Nobody minds being asked, and her turn ons and turn offs are printed on her page here if you would rather check first.
What does going into private involve?
You click through to her room, and her per-minute rate is shown before anything starts. It is one to one from that point, she can see and hear you if you want her to, and you end it when you are done.