I expect your supervisor does know something about your subject. People don't get to be supervisors without having a wide knowledge of areas that relate to their own particular area. A lot of research work has to be self motivated (I suppose lab work is a bit different if it is a joint project) read the handbook to find out what you should be doing, go to the supervisor with some kind of overall plan, ask for advice about the first area you want to tackle and take it from there. You must not underestimate their knowledge, you should ultimately become an expert in your own particular bit, and then you can explain that to them, but I expect that on the way you will uncover bits of info, or some comment by someone else that you think they won't know about, but will find they know more than you do . Also, if you think they know nothing about the area - perhaps you haven't explained it very well to them?