Really easy and cheap DIY project! Perfect for a mirror or window! Easy to do alone, unless of course you need pictures of the process. Enter the 9 year old...I apologize in advance (not that my pictures are that great anyway). ;)
All you need is a roll of contact paper, a Xacto knife, and something to serve as a smoothing tool. I have a little squeegee thing, but credit cards work well too.
Start with a clean mirror! Be sure and prefit the contact paper over your object to get the angle and length right. I didn't do this the first time and ended up peeling it off and doing it again.
Then, for the love of God, do not pull the backing off of your entire piece of contact paper! Just start it at one end, place it properly, and slowly peeling the backing off and stick the paper with your squeegee tool/credit card as you go! I can't imagine how hard it would be to get that big sheet on straight and wrinkle free in one fell swoop!
Next take your Xacto knife and trim off the excess contact paper. Then use your knife to cut the shape of your ghost directly on the mirror. DO NOT use too much pressure! It will mar your mirror. No, there is no particular reason why I know this..... Make your shape lightly! TRUST!
See the outline of him?
Now the best part! Slowly pull off the extra contact paper to reveal your ghastly shape!
You can leave it solid or add eyes, a mouth, or whatever! Use your craft knife to pull out the eyes by picking them off at the edge of your cut.
There were a couple of areas that the cut wasn't deep enough. If this happens, just whip out your Xacto and give it an extra little cut.