How do you guys add a liner to a sheath? And roll the lip?

Soooo I’ve seen a few sheaths that have a “soft” liner inside them. What do you pros usually use for these liners? Also, I like sheaths that have that little rolled lip on the front piece right where the knife is inserted, is this part of a liner that’s just brought outside at the top and rolled over? Does anyone have or know of any videos or WIP’s? Any help is greatly appreciated!!