Any colour piece of construction paper.
You want to make sure your paper is on the horizontal to start , the cuts need to be made on the horizontal.
And then you make 4 small cuts
in each corner go down 2 inches and then cut into horizontal 3 inches, do that in each corner and you will have 4 flaps
I do at this time fold the flaps on the horizontal to make the box for easier , just more for a guideline when you go to fold the flaps in
I fold both sides up picture is just a visual .
Now fold your box .
Fold each flap into the side piece, glue them in place for support .
You are left with flaps, just fold them over first so you have the crease , then glue along this piece as well and fold over to finish your paper box tray.
And.. voila simple and easy to make . You can manipulate the sizing , to make many different sizes , as you can see from my top photo. Just remember to cut along the horizontal .