I made a pair without a pattern.
I used early generation Gore Tex on the top with a cordura bottom. Today I would line them with lighter nylon, which I could coat for the ankle area and leave uncoated on the calf.
I can use a sewing machine, but am no way close to really competent.
They worked fine with a little tinkering, but the real issue was the zippers. I never could find decent zippers. The low grade zipper was the issue that eventually retired them.