Screw the hinge onto the door in the place that it should be. Then trace
around the hinge with a sharp utility knife making a cut about as deep as
the hinge.

Take off the hinge and it should be easy for just about anyone to chisel it
out the area that you just outlined, and you'll have a nice, clean mortise
without a router. Just chisel with the grain toward the center of the area
rather than towards the edges so you don't run over. If you need to chisel
towards the edge, make sure that the line that you cut with the knife is
deep enough

I've done it many times. Use the same method for the striker and bolt
plates.

Your best friend in hanging doors is a hinge bit or "Vix bit" to get your
screws nice and straight.

http://www.amazon.com/gp/product/B00...542469?ie=UTF8