You can also - and this has worked very well for me - do a little affirmation in your head before you fall asleep. Just say to yourself a few times: "I'm going to remember (all) my dreams". This is super easy and very effective. After a few days/weeks I was able to remember several dreams that I had that night. The cheating you mentioned also works very well and you can actually do it a few times with each nap being 10-20 minutes.