How to Make Cardboard White
- 1). Purchase a bucket of white acrylic or latex paint. Both of these paints are water-based, making for easy cleanup, and work well with cardboard. If you prefer spray paint, get one designed for indoor use --- cardboard will absorb most outdoor spray paint, making an even coat difficult to achieve.
- 2). Prepare a paint-safe location. If you want to whiten your cardboard outside, any lawn will work without any precautions necessary. In other environments, lay down a sheet of plastic to protect surfaces you want to protect from the risk of paint splatter.
- 3). Paint your cardboard with a wide brush, laying down enough paint to turn it completely white. If using spray paint, shake the can for two minutes and spray from a 1-foot distance until fully whitened. Wait for the paint to dry before using your cardboard.
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