First read F. Alton Everest's "Sound Studio Construction on a Budget" (or his "Master Handbook of Acoustics", 2nd or 3rd edition--since the 4th is supposed to contain errors) and analyze your room's main resonant modes. Everest goes into lots of commercial and DIY treatment devices. I have designs for RPG-style diffusors, which people sometimes admire as sculptures, and Argent Room Lens clones--please email me if you'd like me to email them to you. If you'll forgive my putting it so, you're in the kindergarten stage, pretty much--but reading Everest will educate you fast. It needn't be ugly though it may not pass for an ordinary room.