the jig bite around here usually feels like a freight train is on the other end of the line. but if the bite is more subtle just stare at your line. naturally your jig wont fall left or right just vertically so any sudden movement or sideways travel just set the hook, hooksets are free. i find it easier to see my line (12lb yozuri hybrid in green) with my polarized glasses on.
it really helps if your line/rod combo is higher quality too so you'll have more sensitivity. i've gone from a BPS bionic blade to a st croix mojo bass and its a WORLD of difference.
honestly i think the rod makes a HUGE difference. I was fishing my mojo bass and a 3/8 ounce jig under a small bridge, then after a few casts i used my buddy's st croix legend elite flippin under the SAME bridge, i felt structure that i didnt even know existed with the mojo rod.
all that expensive equipment aside, 95% of my jig bites the fish just ATTACK the lure.