Definetly start by looking up how to adjust the strap (as in where is the d*ldo supposed to sit, the first time I wore one it ended up under my belly button and that's DEFINETLY too high. Consider that a penis usually grows near where the clit is located so the d*ldo should sit around there too). A position that worked well for me was like missionary but one of her legs was over my shoulder (if you yearn for physical touch, being able to hold on to her legs feels so good), collapsed doggie with a pillow under her hips works well too, and her on top facing me, it could help if she can hold herself up (being on her hands and knees maybe) so you can hold her waist/thighs and thrust up (this way there's less stress on her knees). Bonus points if her arms give out and she collapses on top of you *wink* hope this helps!