I did this for my son's wedding last summer. The centre white square (for the guests to sign) was framed by slate gray (colour of bridesmaids' dresses). I took that part only with freezer paper pressed on the back to give the block stability while signing. I set up a sample block on a small stand as an example, with the pile of blocks and several Pigma pens for the guests to sign. They had to keep their messages in the white and no one wrote on the gray. I then took the blocks home, removed the freezer paper and finished assembling the blocks. We used the blocks instead of having a guest book.
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