Because camo is such a strong pattern, it's best to wear a plain top or jacket. White, black and other neutral colors look great, and adding solid colors can help to soften the overall look.
Don't pair camo pants with other camo or animal print items; this will only start to look busy and overload the eyes. Camo pants can look great when accessorized, so choose a black or metallic belt to complement them or add some simple gold and silver jewelry to jazz the outfit up. For footwear, pair your pants with some black boots or shoes to really complete the look.