I have to say receiving for me is best just laying down, I like 69 for foreplay but to get the most out of oral it has to be about the other person only, I get too distracted with both of us going for it. For him, I'm not particular... he likes when I sit on the edge of the tub so he can watch in the mirror, his own porno. Kneeling is good for letting him be dominant, I like when he sits in the cushy chair in the bedroom stroking it and I crawl across the floor to suck him.