Cycling caps definitely make a big difference. They allow you to keep an eye on the trail or road in front of you while blocking out the offending light. The important thing that you have to do is slow down a bit because you’re not looking as far in front of you. I tip mine a little to the left. It isn’t a political statement, or a way to be cool. Since most lights are approaching a little from the left, it lets me look a little further down the trail on the right side to see what is in front of me.
There are many great places to get caps. Most bike shops have a good selection. They range in price from $10 to $40 depending on what you get. At the high end, you get one that is waterproof and breathable and works great in most weather conditions. Some of the hats are wool and have ear flaps for warmth.
My latest find is the Giro Reverb helmet. It has a visor built into the front pad. It is EXACTLY the right length for shading my eyes from oncoming cyclists.
BUT THAT’S NOT ALL!!!!
Cycling caps have another side benefit too! When it rains out, a cycling cap keeps the rain from falling directly into your eyes. Adjust the brim so that the wind and rain deflect off the brim and go south and north of your eyes, making visibility MUCH better and cycling much more comfortable. Even the cheapest of cotton cycling caps (which I generally don’t recommend for any kind of cool weather cycling) will keep the wind and rain out of your eyes quite well.
Have fun. Try the hats on. See how they fit under your helmet. If the shop you’re shopping in has a bike on a trainer, sit on it and see how the angle and length of the brim fit. My sentimental favorite hat fits my head perfectly, but rarely gets used because its brim is too long and it is hard for me to see out from under.
I hope that helps.
Pete