Did you get the instruction manual with your lens? If not I'd get that (sorry I don't know of an on-line PDF; you may have to buy it).
You can do these combination with only two knobs:
On knob goes from Magenta to no filtration to yellow.
The other knob goes from Cyan to no filtration to yellow.
So , with those two knobs you can make any of the following:
No filtration
Yellow filtration
Magenta filtration
Cyan filtration
Magenta and Yellow = Red (for example Magenta knob on maximum Magenta and Cyan knob on maximum Yellow, etc.)
Cyan and Yellow = Green (for example Cyan knob on maximum Cyan and Magenta knob on maximum Yellow)
Magenta and Cyan = Blue
So that is every combination except any that produce neutral density. You should be able to look through the lens and see the colors. A few minutes twisting the knobs and you should be able to figure it out.
So if you are shooting slide (transparancy color film) and want less cyan, with this lens you need to add red by twisting the Magenta knob to Magenta and the Cyan knob to Cyan.