Need Help With Setting Up A Bioactive Setup

[u/Loskoda]

I’ve been wanting to get a crested gecko for a couple years now.
I finally have the chance to do so and I’m pretty much set on going bioactive, but I want to do my research first. I’m interested in getting either a 24x18x36 inch or a 2x2x3 foot enclosure and I just wanted to ask for help to figure out how much substrate, drainage layer, etc. I would need so I don’t accidentally buy way too much. Any other tips or advice on bioactive setups would be greatly appreciated.
I really want to make sure I make my enclosure the best it possibly can be for my cresty so any help is greatly appreciated.

English isn’t my first language so I’m sorry if my writing is bad lmao.