Being on top

my boyfriend is always making jokes about how he's the one that does all the work when we have sex so he's asked me to get on top and when I do I'm not really sure what to do, even when I'm on top he grabs me and thrusts from underneath me. which does feel good but I want to be able to do things to make him feel good without him having to do any work. 
can anyone give me some tips on what to do while I'm on top?
also I'm a little self concious when I'm on top not only because I don't really know what I'm doing but because I'm not totally comfortable with my body being fully exposed, and jiggling while he has a full view of me.