First you need 2 Scallop Envelopes. Mine are in Melon Mambo here.
Next, cut the bottom flap down to only a 1/2".
Add some sticky strip to ONE of the envelops on the three flaps.
Remove the backing from the Sticky Strip and attach the two envelopes together on the tabs. Hint: at this point you will fold down one of the scalloped edges. However, it looks nicest if you fold forward the one whose flaps are folded back over the other one. If you do the opposite then all the open creases will show.
Next, cut a strip of decorative paper to 1.5" by 8.5" and wrap around the box. I usually adhere to the front with a bit of Snail adhesive then overlap the ends on the back and adhere there as well.
Last, decorate however you want and make some quick 3x3 notecards to fit inside. SU's Mini Square Envelopes (107309) are 3 1/8"x 3 1/8" will fit perfectly. This does not have to be a holiday project and would be great with any of SU's designer papers for any occasion!
I hope this is helpful! Let me know if you decide to try this out. Also, I need to reiterate that I did NOT invent this box but I have no idea who did come up with the idea so I can't give proper credit.