LEARN TO IMPRESSION KEYS WITH THIS VERY INFORMATIVE HPC MANUAL
One of the dying arts is the ability to originate keys using the impression method. Locksmiths don't seem to spend as much time on this skill as they used to. It's still one of the true measures of a good locksmith, right along with the ability to pick a lock quickly.
LC-5 is aptly titled, "Theory and Techniques of Impressioning". The title says it all. You'll enjoy reading insider information about how to make this art a part of your skill set, and you'll enjoy even more putting it to practice.