There's several places...
1) The back of your right hand.
2) The back of your right wrist.
3) Your right forearm.
4) Your right elbow.
Backs of hands are still touching each other.
Initially, I thought that has to be somewhere on your right arm, between wrist and shoulder, but on thinking it through, that doesn’t work, well, maybe your right forearm, so put me out of my misery.
I’ll ask my wife in the morning, and she’ll think for 5 or 6 seconds and come up with an answer, she’s always said, “Jean, you’re undoubtedly intelligent, but you have zero common sense.”
On your elbow
Unless you have a joint in your forearm your not touching the other hand