This DIY is very short and easy.
- felt, one or two colors
- cotton lace or elastic
- magnetic button
- and an iron-on image that I usually use for my tutorials
Cut out one large felt rectangle, 13.5 cm x 20 cm and two small, 5 cm x 13.5 cm.
Stitch lace or braid to the long side of the big rectangle, bending the ends of the tape to the backside.
Stitch lace to one long side of the small rectangles, too.
If you're going to put a magnetic button, then put the mark and make slots now, but the button is left aside for a while.
The sides are sewn to the main part, with lace inwards.
That's all in general, but I ironed on the image, the most important thing here is to find the right temperature when nothing burns and just sticks to the surface:
It works with felt better then with cotton.
Now insert the button.
Everything is ready. You can dress the document. Cheap and cheerful :)