I'm most familiar with Dell Orto - Italians freak u' know!
I think that Mikunis works very close to how Dell Orto's do. If you don't know where you are with the mixture it can be a good idea to start with the standard jetting and take it from there. Then make a 'tape tuner' for your gas grip, with marks for 25%, 50% 75%, 100%. There can be a great difference in what you feel is the throttle position and what it actually is. It take some while to get it optimal.
This manual is very detailed and gives a lot of excellent explanations: http://www.guzzitek.org/documents/carburateur/DellOrtoMAJ01.pdf