Advice to Newbies

Get a least 6 Stillpoint Apature panels for your room get the best ASAP.

OP, good post but what do newbies test their room with if they don't have speakers to play the REW tone sweep with?

My own process was to get speakers I liked a lot and then tested to see how the room could be improved to accommodate the speakers. 

hilde45 offers the correct response. I think that treating a sound room before the actual system is placed there is a reverse way to go. Different systems (especially speakers) have characteristics of their own. And how they interact with the room will be different.

Room acoustics and treatments is very important. But it should be a "fine tuning" step and not an initial one.

EBM giving some solid advice again.

@hilde45  I was assuming that a newbie has made the initial plunge and purchased a set of speakers. Then, after some time, starts longing for better sound. This is where the REW comes in. Before falling down the rabbit hole, make sure your current dissatisfaction isn’t room related.