I made this in less than 10 minutes, including taking the photos. It doesn't look like much, but it works, and you already have all the items you need on hand !
1) An old cardboard box
2) A box knife
4) 2 pieces of tissue paper
5) 1 piece of foam board
First, cut off all the flaps on the box with your box knife.
Next, cut a square on one side of the box. No need to be pretty here, even or straight.
Cut another square on the opposite side, and a rectangle on top.
Cut the tissue into the 3 pieces that already have a fold. Use one third on the top, and tape it down.
This is how mine looks from the inside looking up to the top.
Tape tissue over the two squares on the sides.
Pop in a piece of flexible foam board.
Now, believe it or not, you are ready for the actual photo of your card.
This is the "before" picture !
After the photo has been cropped, it will look like the above. I used all natural light, but you can use flashlights propped outside the sides of the box if you are taking a photo in the evening. Again, you haven't made anything real gorgeous here, but it is quick to make, does the job and it is (nearly) completely free !
Hope that will make your photography just a little easier !