Bicycle Helmet Visor Extension: How to Make a Larger Bill 

Stock bicycle helmet visors are too small and are worthless, especially if you are wearing sunglasses. You need a bill or visor long enough to keep the sun off of your glasses. There's not much in the way of commercial solutions. This do-it-yourself oversized visor can be fabricated and installed in minutes. I bike a lot and I can't live without it.