My cousin and his wife had twins in August. I gave them baby hats at their shower, and when they told my mom that the twins had outgrown them, I sent them earflap hats. Then they e-mailed and asked if I'd be able to knit hats to go with vests they had purchased. I picked up the vests at Thanksgiving and went on a yarn search.
Here is Thing 1's hat and vest. This hat had to meet two criteria: It had to be machine washable, and it had to go with the vest. This one was knit out of a bulky weight acrylic yarn.
Ann Budd's Basic Hat Pattern knit in Loops & Threads Charisma in Sunny Day colorway
Matching Thing 2's vest was a bit more difficult. It's not exactly a hot pink. It's some sort of pink/raspberry hybrid. The best yarn in terms of color was a cotton worsted weight.
Ann Budd's Basic Hat Pattern knit in Bernat Cotton Tots in Very Berry colorway
The pattern came from Ann Budd's The Knitter's Handy Book of Patterns. This book is genius. It's full of charts. You figure out how many stitches per inch your yarn gives you (bulky was 3 and worsted was 5 for me), what size you want the hat to be (0-6 month), and follow the chart where those two numbers intersect. Really, really smart and something I think I'll use a lot.
The only problem that I had was that Thing 2's yarn required me to cast on 82 stitches. I don't own small circulars in many sizes, so I use double-pointed needles for most small projects.
cotton yarn + metal needles = slippery
The only way I found I could successfully knit this was by putting stoppers on every single end of every needle and rotating them around as I knit. It really slowed me down and was inconvenient, but it was the only way to keep the stitches from freeing themselves with every hand movement.
I may need to be rethinking my Christmas list. There has to be a better way.