help with mouse pad sharpening technique

[az rat]

I have heard about it here but have not seen the actual explanation of how to do it . also for a newbie I just got my first asymetric grind busse, its used and when holding the knife point away from you edge down ,which side is flat and which is convex, it was what I consider pretty dull when I got it ,both sides seem flat to me ,the right side just seems to be a more acute angle with more of the finish removed from the right side any suggestions ? thanks