I wear 5.11 "tactical" pants most of the time which have cargo pockets and a cell phone pouch and huge back pockets. As you can see in this pick I am relatively discrete minus the camo shirt and camo bandana having basic OD pants, black backpack, tennis shoes and a tan boonie hat (keep in mind this is the desert). Tan 5.11 stuff is even more discrete I think.

In this pic, my pockets have wallet, knife, lighter, cell phone and some other small items. My backpack has a whole lot of evil stuff (AK 47, magazins, ammo etc) in it but as you can see from the shot of my walking away, I just look like any other hiker.