This earmuff is knitted in rounds on four double pointed needles, as you would socks, so there is no joining or sewing up.
It can be knitted with three different boarders to give three different effects, a garter stitch (as shown below), moss stitch, or ribbing. I would suggest ribbing if you are wanting the band to stay firmly in place as it has a more snug effect, but the others will stay in place too just not as well.
This size measures 50cm circumference unstretched. To make a size smaller minus 11stitches from the pattern, to make a size larger plus 11stitches.
I have written this pattern like a check list so that you can check off each row as you go.