I recently completed the Balsa USA Fokker DR1 1/4 scale. I got a very good look by painting the entire surface with a base coat of light brown (Behr Mississippi Mud) and then dry brush the top with a color called Chocolate cupcake (also Behr). That is a Home Depot paint! It has the green in to match the origonal very well.
The Brush I use to dry brush is a "chip" brush. That is one of those that they have a big box of on the botom shelf at Lowes or Home Depot . Just watch for loose hairs getting in to your work. It is a very coarse hair brush and they sell very cheep.
The key is to work consistantly and patiently.
Good Luck!
Rich