First step decide what you want to do with the tank. If you have an idea of that it’ll help you lock in what equipment is worth getting and what isn’t. Then just be patient and take it slow. It way way easier to just go slowly than it is to battle against a mistake you make because you weren’t.
There are tons of BioCube 32 build threads on here so you can get a solid idea of what others have done and use their lessons learned. I find them amazingly helpful. I’m still a novice but feel free to check mine out.
My biggest regret from building mine out was not thinking about the scape enough before I jumped in and not securing my scape together.