Are your blocks all different sizes? Well it would work the same if they are all the same size to. Just put various sized sashing ,or coping strips, around your blocks. I think it is easiest to break it down into sections.
Say 5 or 6 blocks, arrange them the way you want with different size sashings. then on the next section you want to make it about the same size and just keep fitting the sections together. I know I am not explaining this very well. Here is the link to my chicken quilt maybe you can see how I did it. but I think you would want all the same color sahsings on yours.
http://www.quiltingboard.com/posts/list/17004.page