I don't remember if he has any specific recommendations. I don't know what the best way to test ones abilities would be but the REG (random event generator) paradigm seems highly conducive to rigorous and thorough experimentation. Alas, I forget what the literature says about pseudo-random generators. I can't in good faith recommend psi experiments; on the one hand if psi is for real then we're probably doing it all the time without realizing it (which is I think the typical Eastern perspective), on the other hand it seems like a generally bad idea to go out of ones way to play around with a little-understood perhaps-agentic process. Playing with Thor seems significantly dumber than playing with fire.