I use the Heat & Bond Lite method as well and it works so greatl!!! I prefer Heat & Bond Lite because the Lite will not gum up your needle!!! I also use very a stiff TimeTex instead of card stock and stitching goes much more smoothly. If you don't have TimeTex, use a firm interfacing to replace the card stock.
FOR FABRIC POST CARDS:
Apply Heat & Bond Lite to the face of the card, remove paper and decorate as desired, press well. Then cut a second layer of interfacing the same size to make the back side. For the back side, I cut a piece of solid ivory fabric 1/2 inch larger than the card. Apply Heat & Bond to your card to both sides, remove the paper on ONLY ONE SIDE, and center on the piece of ivory fabric. Iron as directed. Now wrap around your card layer, folding corners until very smooth. Iron according to directions.
NOW, remove the paper on the reverse side of the back. Carefully, stack the two cards together, making sure to have the CORRECT SIDE facing out!!!. Press the two layers together until well bonded. Let cool!
I like to use a blanket stitch to finish the card on all four sides for a very completed look. By stitching in this method, your layers are secured for use! Enjoy!