Originally posted by Chi
+ means increase stiffness, decrease travel by increasing spring tension.
- means decrease stiffness, increase travel by decreasing spring tension.
That would be my guess. Usually you want to adjust both at the same time. Play with the settings and see what you like. I usually like setting mine (RS Indy C) full soft during dirt rides, and full hard during road rides.
A few things wrong here. Increasing stiffness does not decrease travel and vice versa.
There is no travel adjust on the RST fork I would imagine. They are far from the top of the line forks.
The right leg that says "press" is probally your compression adjustment (make it harder or softer). What the L and the S stand for is beyond me. But I am pretty sure that your right leg is compression.
The + or - is Pre-Load.