It had been my sister's sweater. After a round of closet cleanup, she gifted me with a box of her discards, which I was delighted to receive. The sweater was the right size, only it had a number of holes in it. Sure, I could have tried to patch the problem areas, but I was "in the market" for a wool hat.
One step was left, and that was to make the pom-pom. There are many ways to do that. I sort of made it up as I went along, but here is one set of pom-pom-making instructions. (The unraveled yarn remains kinky even now.)
Here's a view of the entire hat, with the pom-pom sewed on:
The last thing to do is to plop the finished product on your head, and to head to a mirror to check out your handiwork!