This is going to be unpopular but my routine doesn't really involve measuring much. I want get the brewing over with ASAP so I can drink my coffee.
Prime the filter with hot water and pour out water
Put in ground coffee, I just use 6 TBSP for the 8 cup classic
Prime grounds by pouring just enough in to stir them up and get wet
Wait for gas to release (should have a nice cone of grounds)
Pour water into the center of the grinds and then circulate as water rises
Wait until brewed coffee gets to the belly button of the chemex
Pour more water in until it is about 1/4 inch to the top
Let drain out and enjoy
I just go a bit bigger with my scoops if I'm looking for more of dark brew. My goal here is to control the output so that when finished I have enough coffee for about two pint glasses. Thy key is that belly button which I'm guessing is the half-way mark.