Instructions which are included on free printable Mothers Day Card:
Mothers Day Card, print and then cut out along the border that is marked with scissors. Then three-fold as you would a brochure: lay it down, blank side up, on a flat surface; fold the front side back; turn over; fold the back inside. This card fits in a number 6-3/4 envelope, which you can found in most stores. This does print landscape.
Sorce : http://www.momsbreak.com/printable/mothersday/free-card-mothersday-supermom.shtml