Home Studio Soundproofing

Right, so I’m planning to set up a rehearsal studio at home, and we’ve chosen this room:

L: 4.5 m
W: 4.1 m
H: 3 m

There’s a window on one of the walls. It’s the only room we have left that’s available, so yeah.
I just need suggestions and ideas as to what I can do to improve it and make it band-friendly…stuff like soundproofing, materials, resonance, where to place instruments, bass traps, etc.

We’re a 5-piece high school band, with drums, keyboards, 2 guitars, and a bass. One of the guitarists is a vocalist too.

I’ve done a lot of research but never really understood it well enough to apply it to the room.

Any help will be greatly appreciated. Thanks!

best thing you can do is get in there and try it,it’s all part of the learning curve,old carpet does a decent job of soundproofing and is cheap