Couple of Items
As it relates to soldiers, primarily infantry and sharpshooters, both sides had units outfitted in green uniforms - Such as Berdan's Sharpshooters and Alexanderia Riflemen (Co A, 17th Virginia). The green helped comouflage the soldiers when operating in the forests of Northern Virginia.

While the Confederate Army was considered the 'grey', as compared to the Yankee Blue, many soldiers were clothed in uniforms that had a butternut or brownish color to them. This was considered a good color when moving through the woods, as it sorta blended into the back ground.

Prior to the Battle of First Manassas, Bull Run to them damn Yankees, the Confederates at their defensive positions around Centreville, Va prepared what were call 'Quaker Guns.' These were logs, cut to look like cannon, and placeed on artillery limbers or other rolling stock. This gave to the Yankees the appearance of a more heavily fortified postion that what was really there.

Hope this helps

JIMT