Start with standard large pallet crates. These are Crates and Pallet crates from Home Depot.
Add 1×4 furring strips to the sides to give the crate some more structure and some wood for the drawer slides to bite into.
Paint the crates to your choosing. I used a blue semi-gloss spray paint from Rust-o-leum for my finish. You really don’t need to paint the backs or the sides that will be facing the walls if you are trying to save on spray paint.
Mount the drawer slides to the wall using one easy trick. Go to the post link below to see the super simple way to do this and keep everything straight and lined up.