Ah, I just took a quick look (I don't really need a tutorial), but here's my opinions:
-Have text to tell what to do, rather than just doing it with the mouse. This is a MUCH better alternative to using audio as john.d.h suggested, since its easily understood and can be viewed muted in public (school, anyone?).
-John had a good point on using numbers of course, but while more accurate, you generally need to scale it by hand first, so sorry john. Best to scale by hand to get the idea of what number to use, then use that number, then apply math to have everything positioned perfectly.