I made one of these boxes about a year ago and it's posted in my gallery under splitcoaststampers. Here's the measurements:
outer layer: 12 x 12. score every 4 inches from all sides. Cut out the 4 corners.
Mat: 3 3/4 x 3 3/4.
middle layer: 11 x 11. score every 3 3/4 inches from all sides. Cut out all four corners.
Mat: 3 1/4 x 3 1/2.
Inner layer: 10 x 10. score every 3 1/2 inches.
Cut off all 4 corners.
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Mat: 2 3/4 x 3 1/4. Center of box: 2 3/4 x 2 3/4.
LID: 8 x 8. Score 2 inches from all four sides.
Hope you have fun making these cute boxes!
I'm dying to make a Hello Kitty one when I get a chance! :0) Have a good nite!