It's pretty simple and really a show stopper. Everyone oohed and aahed over it.
Make your favorite cake, frost it (don't worry about messy, it wont even show) then press KitKat candy bars to sides of cake - I broke each bar in half. Each half had two bars, so I just did two bars at a time. Some people just fill the top with m&m's, but I thought it would look even cuter with a little pattern. I just added a ribbon with double stick tape to make it look festive!