Wear something bright, so that motorists can see you.

Never forget, that most people who are driving cars (who are non-cyclists) don't care too much about people on bikes. Assume that anyone behind the wheel of a car is texting, talking on a cell phone, eating, yelling at their kids, but NOT looking out for you.

Bright jerseys, like a Pearl Izumi screaming yellow, or any obnoxious (I have several) shirt with a design that you like will do.
Make sure that it has reflective properties if you are riding early or late in the day.