A novelty test to too see if you're doing it right:
Check the oil visually before you make your run (well, level is obviously important, but appearance is what you're after)
Usually it'll be kinda ikky black, or at least dark.
Take it for a good blast and check the oil again.
Done properly, the Italian tune~up will have the oil looking pretty much as good as it does coming fresh out of the bottle.
This is a result of things finally getting up to good temperature and held there long enough to burn all the contaminants out of the oil, leaving just the nice clean oil behind.
(yes, oil is supposed to get hot enough to cook the poo out of it. You just don't want to burn it)