Here are some tips on how to paint mass quantities of troops in a style similar to those pictured on this site.

Painting Tips - US
Mount about 10 figures at a 45 degree angle on hobby sticks using white glue

Prime with Chalkboard color black from Rust-oleum's Camo line. Paint in details such as rifles, canteens and faces. Use Vallejo Dark Prussian blue on coats and Andrea Blue on britches. Coats get a touch of Vallejo Prussian Blue for coat highlights. Use Andrea Blue with a little white mixed in if you wish to highlight the pants. No wash needed for the Yanks.

Mix black, Burnt Umber and a little smoke (All Vallejo) with water until it is soupy and paint all the bases brown. Let dry, remove from sticks. I use flocking gel mixed with the same colors I paint the bases with a little more black as the gel is white. Before the the gel dries, sprinkle on some of your favorite static grass.