How to Make Poster Board Look Like Parchment Paper

Fold and crinkle the poster board as much as you can to give it a slightly worn appearance. This will also weaken the paper in spots so that it soaks up more coffee.

Pour a pot of brewed coffee into the large, shallow tub. Immerse the poster board into the coffee. Depending on the size of your poster board, you may need several pots of brewed coffee to cover it. Allow the poster board to sit and stain -- a minimum of a few minutes up to a couple of hours. The longer you leave the paper in the coffee brew, the more thoroughly the paper will stain.

Drain most of the coffee from the tub so only a little bit covers the poster board. Sprinkle a liberal amount of instant coffee granules onto the poster board. The granules become wet and add much darker splotches to the poster board surface. You may want to concentrate the granules around the outside edges of the poster to create a darker stained border. Let it sit for a few minutes.

Daub up the excess coffee granules with some paper towels. Lightly smear a few areas to help the granule stains to blend into the background.

Lay out some paper towels on a water-resistant work area. Remove the poster board from the tub and lay it on these towels.

Dry the poster board with a hair dryer. This may take up to an hour or more depending on the size of the poster board. It is done when it is dry to the touch or the edges are starting to slightly curl.