In my opinion, the best reality check is the memory check. You either do it on its own, or do it to back up other rc's simultaneously. Check your memory; think about your situation - how did I get here? Do them properly, otherwise you'll do it bad in the dream.

E.g. of a bad reality check/memory check:

Waking memory check: "Oh, of course I am not dreaming."
Dreaming memory check: "Oh of course I am not dreaming."

Oh and don't pinch yourself - you might wake up if it's a dream!