my personal preference is to set up doubles with providers (i) that I've seen several times and have clicked with individually, (ii) that are actually friends with each other IRL, and (iii) that are actually into playing with each other as well as with me.
The sex is fantastic and the natural, playful, easy-going atmosphere is amazing. It's effortless and it's wonderful.
Before 2015, I had only done one double. During 2015, I did 7 under the above formula, with a fantastic, extended circle of provider friends. They are all beautiful women, beautiful people and great friends to each other (and me)!
To the extent the above formula is difficult to attain, my priorities are as follows:
(i) MUST HAVE
(ii) GREAT to have
(iii) NICE to have
In that order.
I suspect some would reverse prioritize (ii) and (iii).
Find a favorite provider that you truly enjoy spending time with. When you are sufficiently comfortable with each other and can be open, ask if she has any friends that she enjoys doubling with. See that friend, and off ya go.
Good luck!
el dud