Maybe I never noticed as my hair is so messy (intentionally) and full of product nothing gets through to it :). I haven't used my sewing machine for such a long time now - I used to make lots of clothes and soft furnishings but then life and knitting got in the way and I stopped but after making this today I think it's time I started again.
After making sure the lining was wide enough - I added an extra 4 inches to the width ie hat will stretch to 24 inches - so cut the lining to 28 inches. I also added to 3 inches to the length as you only need approximately 3/4 inch top and bottom to turn under. That ensured there was plenty of room as satin lining does not stretch. I also attached the lining to the top of the hat with a few stitches so that it can not slip around once on your head.
Photo below is of the hat inside out with the lining.
This is a photo of the hat completed.
I had wondered about how to sew the lining to the hat to make sure it stretched enough with the hat when worn. I found this great blog post by Playinhookydesigns about using a mannequin head when stitching the lining to the hat, I know she was using a stretch fabric to line her hats with but the principal was the same and it worked. Sometimes the answer is staring you in the face, as my mannequin head is next to me in my office/craft room all the time!
Now it's on it's way to it's new owner in time for Winter - it's always winter somewhere in the world :).
Now should I go and sew or knit that is the question!