I've had quite a few requests for this and have finally adapted my Yin Yang Valentine Card into a printable version, which is easier for hand cutting. The two hearts still tuck under one another and open up nicely.
The flower blossoms no longer need to be intricately cut because they're printed now, saving time.
In order to achieve the finished size of 5" x 5", the card needs to be printed double-sided on a sheet of 11" x 17" (tabloid) card stock. This can be done at Kinko's or a local digital printer. One card fits on one sheet. The envelope needs be printed on an 8.5" x 14" (legal) size sheet.