ORIGINAL: IMAC781
This is UNSAFE but I would hold the bird's skids with one hand and throttle up the Tx with the other; give a little pitch input, see what happens. This is more of a "real life" test since I could lift the heli a bit while running it up to unload the rotor head. See if I feel the pitch change when I should only feel cyclic. You didn't get this idea from me.
Actually, I recommend not holding it by the skids, but rather the flat spot where the boom meets the frame. That is a much more secure place to hold the heli. The skids can slide out of the frame sometimes. You wouldn't want this to happen while doing a run-up test!
This is how I check blade tracking. I hold the heli with my right hand by the flat spot where the boom meets the frame, then I pour on the gas with my left hand. I can then move the heli around until I can find a spot where I can see the marks on the tips of the blades clearly.
Just make sure you stay focused on what you are doing, and don't let the rotor hit your arm or something. Don't try to do it with a crying baby and/or barking dog under-foot or something
