Self Mailing Heart Valentines!

Isn't this so cute!?
I saw this on Janet Wakeland's site and she said they demonstrated it at Leadership. I had never seen this before so I just had to try one! You can mail it just like this, the big heart turns into the envelope!
The paper in the center is 4 1/4" x 5 1/2" cardstock and the outside heart is one 12" x 12" piece of DSP cut into a heart shape. You'll have to freehand this ladies, sorry! Also the paper I used is retired, I am trying to use some stuff up.
Here is a picture of it part way open: