One of the most important tips to safe cycling is to be as visible as possible to cars and pedestrians. In addition to head light and rear light I also attach a rear light to the back of the helmet for added visibility. This is a simple hack to add a rear light without zip ties or duck tape for a clean look. Note, this may not work on all helmets particularly ones with adjustment dials.
Things you'll need:
Rear bicycle light
Step 1: Step 1: Measure
Measure the width of clip on back side of light and the gap clearance to determine the amount of plastic you'll need to remove from adjustment band on helmet.
Step 2: Step 2: Trim
With sharp knife slowly whittle away the amount of plastic necessary for light to snugly fit onto band of helmet.
Step 3: Step 3: Assemble
Slide light onto helmet band. Safe riding!