I can only find small Google-pictures of that easily right now, but attack is bottom left, and threshold is top right. Top left is 'level', maybe equivalent to ratio, but I'm not sure. I use an Oberheim GM-400 rack unit for mine..
Doing this by ear is best, there's only a few controls. The idea is to get them so if you play rhythmically, emphasising certain beats like a drummer uses a snare drum, you should find them hard enough in sound compared to the less-strong notes. There may be more than one combination of settings that works, so trying it is the only way to be sure. Just don't lose track of what you want from it..
A lot of the time it's not just EQ that helps cut through, but dynamics, which is what the compressor helps with most, especially before overdrive. Less overdrive is needed to get the same edge.