What works best for me is to just ask my self what it is that i want to do. I'm still working on making it routine for when i become lucid. First i become lucid, make sure the dream is as stable and vivid as i can make it, and then ask myself,"What is/are my ld goal(s)?" It helps to make sure that the ld goal you have in mind is in your long-term memory rather than the short-term, because it seems short-term memory is lacking while in an ld. Anyway, i believe if you can make this part of your when you get lucid routine, you should have a much better chance of remembering what it is that you want to do.