Paper( lots ), at least three colors of paint ( one of which yellow or white ), paint-brush, some water, glue, card stock, small paint brush and a lot of books.
P.S. This is my first instructable, so tell me if I did anything wrong!
Take the three colors of paint and dip one of your paint brushes into one of the bottles of paint. Then make big dots of that paint on the paper. (Be very generous with the paint, you want to have no paper showing at the end.) Do the same with the two other paints and make sure you used either yellow or white for one of the paints. Finally, take your big paint brush, start from the corner and brush diagonally all across the paper. Be sure to only brush each area once or twice but no more. You want to make sure the paints are mixed and not blended. Now set your paper aside to let it dry. I will be calling these papers "paste papers".
Fold the top corner of the paper as shown in the picture and cut off the excess paper as shown. Next, fold the square the other way diagonally. Unfold the paper, flip it over and fold the paper vertically and horizontally. Finally, fold the diagonal folds out and the horizontal folds in to make what is shown in the picture.
Repeat step two three more times and then glue the "sections" together as shown. Make sure the "sections" are all the same way.
Now your "paste papers "have probably dried, so take your "sections" and trace them twice on the card stock. Then cut out both of the tracings and cut out two larger triangles on the "paste papers". Glue the card stock over the "paste papers" and then glue the corners of the "paste papers" onto the card stock as shown. Next, glue the edges of the "paste papers" onto the card stock as well. Finally, put both of the "covers" under some heavy books for a couple hours.
Take out your "covers" from under the books. Then take your "paste papers" and cut out as much as shown. Next, glue the spine and the "paste paper" together as shown (again). Then, glue the "cover" to the "sections". Do this with the other "cover" to. Then glue a smaller triangle of "paste paper" to one of the "covers". Finally, put this under the heavy books again.
Take your book from under the other books. Notice how I'm saying book. YOU ARE DONE!!!!!!! Make any adjustments needed.