I’m embarking on a nice winter coat, but it’s a very old pattern and does not specify what kind of fabric I should be using for the underlining. The underlining is being basted to each piece of fashion fabric prior to sewing. My other fabrics are a medium weight wool blend and a nice quality coat lining for the inside. Does anyone have any idea of what I should use for the underlining? I don’t even know what weight of material it should be, and I’m inexperienced in coat making.