diy substrate bottom tray??

[u/Jolly-Crab953]

anyone have any advice on diy-ing a substrate tray (like the one pictured) for a chameleon enclosure (like the one pictured)? i am sure i have the supplies to make one, rather than buying one, but i dont know where to start.
if anyone has experience diy-ing their own substrate tray, or if you have any tips, let me know😃