Toroid Clip from a Clothespin

I've used this handy little holder for hanging onto a small toroid core, while looping the wire through it.

Essentially, start with an ordinary spring clothespin (about a buck a package at the 99c store, or even most supermarkets). Use a fresh one that hasn't lain out in the yard and started to rot; those fall apart.

I take a little X-Acto mini-miter saw and cut the angle opposite what the stock clothespin uses. I don't want to slip over a shirt on the clothesline, I want to have finger room around the tip of the jaws, with the flat holding the little core. I sand down the sawn edges with sandpaper or an emery board (away from the work area) to remove any splinters.

Now grab your core and put it into the jaws, so the center hole is mostly clear, and start counting turns, pulling each one just snug as you go. Remember, one time through the doughnut hole is one turn.