Gatco Gatstix use advise

[dextersp1]

I got the Gatco Gatstix with the white and gray ceramic sticks for when I'm traveling.
The instructions were not very good that came with it.
A couple of questions:
White = Medium?
Gray = Fine?

Any suggestions for good sharpening?
It is best to use heavy or lite pressure?

I have the Sharpemaker for home use.
thanks