I use to do the nose RC all the time, but I havn't done it in a long time because after I did it a bunch it would mess with my ears (and it failed a couple times).

My now (and 100% reliable) RC is looking at my hands, at the grooves in them, counting my fingers(this helps a lot), and rubbing my hands together.

Also, try to remember how you got to where you are. Where you were 5 minutes, 30 minutes, an hour, 3 hours ago, etc.