first the basics, 1= 1 moa and then what does each of the 3 lines between 1 and 2 equal, 1/4" as in 1/4 inch per click?
If I needed to come up 3 inches, (3 moa) I would dial to #3, yes?
Assuming you are zero'd at 100 yards. If you needed to come up 3":
At 200 yds, come up 1.5 MOA
At 300 yds, come up 1.0
At 400 yds, come up 0.75
Get the idea?