Add foam panels to your walls. Use these panels to spot-treat your room and tame room reflections. As an alternative, the foam pads used top of mattresses can be substituted to help deaden the sound of a room.
Add furniture to the room. A cloth couch or chair will help absorb sound and deaden the acoustics. Adding additional pillows and blankets on top of this furniture can help absorb sound further.
Add carpet to the floor. If you have hardwood, tile or linoleum floors, add area rugs to help with sound-deadening.