Are you putting sashing on the edges? Or will you have a border?
Usually you add sashing to the right and bottom of each block.
Then add to the top and sides if that's what you want or put a
border all around. If you add sashing on all four sides you will
end up with double sashing. Here's a link to help you. Draw it
on graph paper then count how many sashings you need.
http://www.synthcom.com/~val/Quilts/...ngSashing.html