Hi! I did these for a friends baby shower. What I did was I got a paper cutter (cheap one from Michaels) and got scrapbooking paper that was velium clear, and another that was yellow with baby footprints. What I did was I set the printer settings to print the size of the chocolate bar, and then placed the clear velium paper ON TOP but a quarter of an inch larger so that the yellow was smaller than the clear but the words came through making it look like it was on it. It was really simple once I printed it and looked like I had them done from a gourmet shop!
You can also do them the easy way, where you just print it on paper and use the small mini candy bars... like this: The easy way to do this is to set the margins to the exact settings you need...