I have no preference in jersey colors, other than disliking team-type jerseys or prominent logos. I prefer solid colors or fairly subdued patterns. I buy whatever's on sale -- white, green, blue, hi-viz yellow. They all have some reflective trim, which helps. Especially some Garneau jerseys, which use a reflective material that appears grayish-black in daylight but is highly reflective white at night under headlights.

I avoid black jerseys, mostly because it's so hot in Texas summer, although it doesn't appear to affect folks I know who do wear black in summer daytime rides. I'd like to claim colors pop a bit better, but my favorite green jersey probably blends in with roadside foliage.

To me, observing other cyclists, helmets seem to be the most important visibility element in daytime. I usually get white helmets, although one has hi-viz orange on the rear, and my other Bell helmet is hi-viz yellow.

If I really wanted some hi-viz kit I'd probably go for socks, although I prefer ankle socks. So my hi-viz yellow trim ankle socks are a waste of effort because the color is hidden by my shoes.

I almost always run lights, day and night, including on my helmet. I might make an exception for one short loop route with little traffic, if I'm doing intervals in daytime. Sometimes I'll skip most lights for those sessions, although I'll still use a Cygolite Hotshot or Hotrod blinky on the back since they weigh almost nothing and aren't an aero factor.