If it is an appliqued blocks, you just need to enlarge or reduce is to the correct percentage. But that would be too easy. Read this article from here and see if it helps.
http://www.quiltingboard.com/resources/article-27.html
if you still need help, PM me with the name of or a picture of the pattern for the block and the size it is now and the size you want it and I will do my best to wak you through the steps.