Originally I was going to make a Barbie head necklace but I couldn't find a spare chain to put her on. So I decided, why not make her into a key chain instead?

It's easy as can be.

Take Barbie and of course - take her head off. Sorry Barbie..you provided me with fun as a kid...it's nothing personal.

This part is optional but you can customize her like I did. You can't really see from the photo (I need a new webcam) but I used liquid eyeliner and lip tint to add pink and black streaks in her hair. Once I was finished with how she looked, I used a wide needle to make a hole in her neck.
Then I looped the jump ring through the hole and then simply added a keychain onto the ring and voila!
Done :)