If you have an unusual shaped cookie and no cookie cutter, what is the best tool to use to get a nice clean cut? And what do you use to make a stencil? Would you use thick cardstock?

AI have made my own cutters out of ez foil pans. Printed out a template, cut the pans into strips, and molded it around the template.

Depends on how many cookies you need to make. A few? Cardstock or foil should be fine. A lot? See if you can get it made by a company that does 3-D printing.

Thank you for your reply.  What is a lot.  I was looking at about 50.

just depends on how many you want to sit there and cut out -- me i would make a cutter for 50 -- 

you can look online for how to make your own cookie cutters -- amazon and other places sell cookie cutter kits too