[MikeBmusic]

As Jim says - 2" panels are more typical for ceiling cloud and point-of-first-reflection trapping. Position of these should be based on the 'mirror trick' - sitting at your normal listening position, place a mirror on the side wall and move it until you can see the monitor speaker, that's where your side panels should be. 2'x4' is typical size used for this. Instead of making huge 4' x 6' panels, which are going to be unwieldy, you might consider making 3 2'x4' panels instead.
I think your question about the dresser was about the hard flat surface becoming another reflection point on the side, but the top surface is not going to bounce sound waves directly at you (the dresser's front might, though.)