How to Make a Cooler from Insulating MaterialThere are lots of ways to make a homemade cooler using readily available insulating materials. Using a lidded box, foil, and recycled packaging materials, you can make a small, simple cooler. For a larger, more effective design, line a cardboard box with foam board. If you need something more portable, you could also sew an insulated lunch bag to keep items cold when you’re on the go.