Well, for RC there are a few favourites, being:
Clock RC, look at the time in a clock, look away and back, is the time still the same?
Nose pinch, pinch your nose, if you can still breath, its a dream.
Memory RC, "how did I get to where I'm?" "Do I remember waking up?"
And overall, just awareness is what seems to work the best.

Also, when did you start the RCs?