GW paints whilst great, are not that good for Camo schemes.
I recommend you invest in Vallejo Model colour range.
http://www.acrylicosvallejo.com/en_US/wwii-german/family/15/16
I would buy this, it's probably $30 dollars or so?
If I were you, I would paint the trousers Camo Biege, and then drybrush the miniature with a lighter shade of stone, or Tan / Kharki.
Also, makesure the flesh is nice dark to give the look of Sun-tanned, darkened Troopers!
Almost looks like a modern US trooper circa 2000 , just add an M16 or M4. !