Leave it on the dresser or next to the envelope if it is still out.

I do it exactly like that. Doesn't seem at all rude to me.

When I meet someone for the first time I bring a second envelope with a Thank You card in it, along with what I might tip.  If at the end of the session I want to give her the tip I hand her the second envelope; if not I keep it in my jacket pocket.

Sometimes I might tip with cash and have never had a lady think its rude but most of the time, especially with someone I've seen before, I have a gift card in a little thank you envelope ready as a tip. More often than not the lady has responded that it was a sweet and classy thing to do.

I hand the lady the money. Never got a complaint or saw sign that she was disappointed in how I delivered the tip.

I usually just leave it on the dresser while we getting dressed and say nothing.  However last week I was doing a role play scenario of a boss interviewing a job applicant.  At the end of the session I said this is your first bonus.

and I have done my research and know I am gonna have a good time, I bring gifts, which if you have read my reviews or posts, you already know about.

By doing research, you should know if you are going to have a great time or not.  IMHO, this is a must.  

So, I can't help you on tipping.  But do your research for all your dates.

Swim

A lot of interesting hint.
Thank you everyone!

I've only seen two providers in my life,(although the same one many times!)and the first time I handed her another envelope with the tip in it.A few times I just gave it to her sans envelope.Once or twice I gave it to her in a card.The inside was blank but I wrote a sentence or two telling her how much I appreciated her and our time together.
AB