I think you will need a stabilizer of some sort...usually you would hoop the stabilizer and then use a temp spray adhesive to attached the card to the stabilizer then stitch...usually I glue another piece of card stock cut to fit the inside of the card to cover the stitched area so when you open the card the stitching doesn't show...
I have used wss on the back of the paper but it did not work out as well as I hoped
That's what I do too - either line the front with another sheet of cardstock or stitch on a separate piece and aplpy that to the card.