Qubes OS Best Practices

Hey Guys, hope you’re all good and safe.
My question is simple : What is the Best Practices with Qubes (setup firewall, able to install App directly in Disposable and being persistant …)

Hello and welcome to the community @Zilla .

As with all other software, with Qubes too the best practice is to start with reading docs and this forum. The difference is that these resources are probably better than most of other software developers and community provide.
It will open a wonderful world of essentially infinite possibilities to merge experiences and practices even of other OSs. Once sucked in, you will realize how superior Qubes is, because it looks at the things from the totally different level - higher one. And from the heights, the vision is much clearer and the sight is much wider.

So, there is simply no better practice then to start reading following resources.

I have no doubt reading will be indeed rewarding.