h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Clasp the hands as in the classic twiddle position. Then place the tip of the left index finger on the tip of the right thumb, keeping the tips in contact lower them towards the palms and touch the tip of the right index finger to the tip of the left thumb over top of the first pair, separate the first pair, bring them over top of the second pair while lowering the second pair towards the palms, join the first pair of tips again and repeat the pattern rapidly.
When done rapidly the fingers rotate around each other and the thumbs simply move up and down. Though simple in action it appears to an observer to be very complex.

It appears to this twiddler to be very complex too ...

Somebody care to untie my fingers for me?

Huh?

A photo is worth a thousand words but that is not an option here.
I apologize for my lack of clarity.
If your hands are clasped loosely in the standard twiddle position (fingers interlocked, palms inward) and you place right index finger tip to left thumb tip and vice versa, one pair will be above the other. Separate the lower pair and and re-unite them above the other, repeat as quickly as you feel is warranted. Well, it seems simple to me anyway when I do it.

I only seem to be able to do it slowly ... guess I'm just a twiddle purist ...

Thanks but I can't get them to move. I must be a traditional twiddler.

Maybe I should chop the tops of my index finger off ... that'd make it easier ...