Sram Rival downshifting

My Orbea Onix has Sram Rival groupo including shifters. I have had this bike since December and have averaged 120 miles / week since. But, for the life of me, I can’t figure out how to downshift one gear. If I go too light, it upshifts and if I go too heavy it downshifts 2 or 3 cogs and I have to upshift.

How long did it take ya’ll to figure this out or am I just clumsy?