I really needed a case for my pencils and I love paper crafting so......
The pencils are separated with cardstock. To make the dividers cut a 12x3 piece of cardstock and score at every 3/8" across. The first section will lie flat in your case, then the next two will be taped or glued together to form the divider. Continue across the piece, folding your score lines. Crease them with the bone folder to make them lie flatter. This will leave the last section facing upward as half of a divider.
Then cut another piece of the same cardstock 2 7/8 x 3 and repeat the scores. Glue or tape the first section to the last section of the larger piece you just completed. This forms another divider. Continue with the rest of the scores as before. This will give you a spot for each of the thirteen pencils.
I used tape to place across the back and attach it to the inside of a standard stamp case.
I placed the box flattened out inside the plastic sleeve on the back. That way I can still check the name of the color, but still be able to see my pencils from the front.
Hope you like this idea. Let me know if you have any questions! Have a GREAT day!