I'm not sure if there is any particular spell for lucid dreaming but if you have window 8 on your computer I suggest you go to the windows store and search lucid dreaming. they have a app on there that gives information on the subject and some tips on different ways to learn how to try. I'm not sure whether they work or not though because I haven't tried them myself. I stumbled across them a few months ago when searching for various occult subjects.
I have found the best way to lucid dream it to write a letter "A" (for awake) on one of your hands and evey now and then though the day look at it so when you do it in your dream you will know you are asleep and gain control
There is a cheat way of sorts though, what you do is record a message of you on you phone saying "(name) you are dreaming .. take control" and set this to go off an hour and 15 min (to give yourself a few minuets to get to sleep).