I’ve been making paste paper and tearing into book size pieces, and pasting other things on top if it.
Paste paper is a concoction of wheat paste, or cornstarch, and water and pigment. You can use acrylic paint for the pigment, or watercolor, or gouache, or even powdered poster paint pigment. I’ve been running it through the printer after its dry using scanned images over the paste background.

The red background of this paste was made using a vintage piece from an old erector set. You can see the little circles at the top of the photo from the edges of the metal piece. I used a scan photo and ran it through the printer a couple of times trying to get some handwriting to show from another scan. It doesn’t show clearly enough, so i have another idea for it.
These images are cut from drawing paper weight paste paper. They are just laying on top of a large sheet, I intend to use them later, just not sure how yet.

This scanned image is used over a piece of brown paste paper – its actually darker than this photo shows.

If you would like to try some paste paper its very simple. I used 1/4 cup of cornstarch and blended with 1/4 cup of water, add this mix to one cup of water and cook ’til you get a nice custardy mixture. Keep stirring so it doesn’t stick to the pan, and try to blend it so no lumps form. Take off the stove and add 1/2 cup cold water. It might look too runny, but it thickens as it cools. Put a few tablespoons of this mixture in small containers, I got mine from the $ store, and then add your color and stir up. The recipe says to dampen your paper – but I didn’t I just painted on the color using a brush, or my fingers, or a sponge applicator. The the fun began of making designs in the paste with various items. A comb, making straight or wavy lines. Rubber stamps, or handmade stamps cut from potatoes, or found objects such as leaves, or rocks, sticks or whatever you have around the house. The paste mixture should be thick enough to hold the impression that you make giving it a kind of 3-D look. You can save the paste covered in the fridge for a few days if you want to use that particular color again.
I’ve made it before to use as wrapping paper, but you have to use a lighter weight paper so it doesn’t crack when you fold it around a package. I used plain white kraft paper for this – once again, from the $ store. I’ve also used the back of regular leftover wrapping paper. I find that my colors sometimes come out more muddy than I wanted – I suspect I was too anxious to add more color without waiting for the bottom layer to dry a little.