Did you mean you are actually constructing your room right now or just prepping an existing room? If you are building a new room from scratch like I did I HIGHLY recommend consulting an acoustician first ! If your room is smaller like mine a professional can design it so it can punch way above its weight. Im so glad I went this route. Jeff at hdacoustics is excellent and very reasonable for the design cost. You won’t be sorry. Good luck !
After the room I would do speakers then components then cables etc