I like to think I'm fairly capable in the bedroom but one thing I've never understood is the process for woman-on-top 
Whenever I try straddling my DH I basically end up shuffling back and forth a bit, not really getting (or giving!) any pleasure and it all feeling a bit heavy and clunky. The only way I've managed to get DH off that way is to basically hover over him supporting my own weight while he does all the thrusting and grunt work (excuse the pun).
Am I doing it wrong? Is there a certain angle or technique I should try? How do you settle into a pleasurable motion that doesn't just feel like you're hefting your entire bodyweight back and forth with nothing really hitting the spot for either of you?
Without the incentive of actually feeling any pleasure it's hard to work up any real speed or momentum, but it's something I'd love to learn how to do properly!
FWIW our usual "finishing" position is me underneath, as I find I need to keep my legs straight and quite taut in order to squeeze everything together and "upwards", if that makes sense...