The SRAM click box is adjusted by having the gears in the middle of the 3 gears and then from behind the bike check the yellow needle is exactly between the lines. It is adjusted by rotating the barrel adjuster in front of the click box.

Here is the link to a PDF on the hub

the dual drive components
https://plus.google.com/photos/101486801025514137400/albums/5223098580972920721?banner=pwa