I have several old Simplicity doll clothes patterns, a couple of which show fabric shoes.
Also, Joan Hines has a book called "Shoes, Slippers, and Sandals" which is available thro the Newarkdressmaker catalogue.....I'm going to order it.
For my first attempt, I used the sole pattern from Simplicity. since then, have searched the web ....voila...a rather good tutorial with pattern. http:/www.snsdolls.com/pattarch/dollshoe/shoemain.htm
No one recommends a hot knife....lol.