I'd get pictures of these people, put them on as your screensaver. If you have pictures of them in your room, awesome. Make them conspicuous, and maybe move them around every so often. Leave slips of paper around your room/house that say their names, or maybe just "friend". Every time you hear one of their names, every single time you think of these people, stop everything that you are doing and RC. Keep this up and I think you'll get lucid quickly. Once you've determined a consistent dream sign it's pretty easy to train yourself to become aware of them