My version is 3 inches wide and about 20 inches long, but you can make it as long as you need to fit snuggly around the head you want to cover.

I worked mine with two strands of worsted weight yarn held together. (Something from the stash.)

This pattern was on About.com (which no longer exists) and has been deleted from their site, but for now it can still be found on the Internet Archive. They redirect and delete pages a lot so you may want to download/print to save.