I used designer series paper, but I believe the box would be nicer if made of cardstock. The first thing I did was score both top and left side both at 1 inch and 2 inches. Then, because I wanted the base to be 4 by 5-1/4 inches, I scored (for the 4 inch direction) at 6, 7 and 8 inches and cut at the 8 inch score line. Length side (tall in the photo), I scored at 7-1/4, 8-1/4 and 9-1/4 and cut at 9-1/4.
Then, I cut the corners for smoother folding. I removed the box in the outside corner (as shown at the bottom left) and the box in the middle. See the top left corner to see my horizontal cuts at one inch. Then, you just cut out the square.
Time to fold: Gently fold each of the scored areas if you are using dsp. If you are using cardstock, you probably should use your bone folder to make neat creases.
Fold in the short sides of the box (top and bottom -though the photo turned when uploaded).
Fit the dividers into the box.
At this point I put a drop of Tombow green capped glue at the junction points of the dividers and the box to adhere it well.
Box Top: Cut your PeekaBoo die cuts and arrange them on the 4 X 5-1/4 "lid" top layer. I traced the openings with a pencil and punched out the holes with a square punch smaller than the holes by punching more than once.
Next, layer the top lid layer over the larger 5-1/2 X4-1/4 inch lid base and punch out the openings again. If you try to punch two layers of cardstock, you will likely ruin your punch.
Now add half width pieces of sticky strip around each window and attach the peekaboo frames.
Put more Tombow glue all over the top edge of the box base. Let it sit a couple of minutes to thicken.
Place the top onto the base and hold it down with some objects. :)