My Very Effective and Simple Reality Check
This is the only RC I use anymore, and it is very effective. I will admit that it may be best for people who have already had a couple dozen LDs, but it won't hurt a beginner to try it. I think beginners should not stop doing there current RCs because active ones make you pay attention to the concept.
A problem with RCs is they may be inconvinent or make you look crazy. I say this is maybe for slightly more advanced dreamers, because using magical type powers in a dream, takes a little practice.
I have practiced levitating in my dreams and can always do it anymore if I try. I do not tend to use super human powers by just imagining it. It seems like I feel a certain way when making a power manifest, kind of like energy flowing through me. So, to levitate I kind of bring a feeling up from below me that lifts me up like on an updraft.
Now that I can almost always levitate in my LDs I use it for my RC. Many times a day, any time I think about it or see anything even a little odd, I attempt to levitate. I just picture that feeling of an updraft I feel in the dreams.
Guess what? It never works, even a little, if I am awake. Often, I see something odd, and naturally try to levitate, and wow, sure enough I lift right off the ground! Then, bang, I am lucid and floating 2 feet off the ground in a LD.
The great thing about this RC is I can do it even a dozen times a day, without having to move at all. Even, in a crowd, I just try to float, and no one has a clue.