Hair tie or rubber band around the brake lever is all you need to make a bike parking brake.
Step 1: Apply the Brake
Close the brake lever with one hand while looping the hair tie or heavy duty rubber starting at the end of the brake lever and then around the handle bars.
Step 2: Secure Brake With Hair Tie.
Loop the hair tie around the handle bar while keeping the other hand on the brake.
Step 3: The Bike Is Now Stable.
That is it, now your bike is stable and will be less likely to fall down when it is leaned against a pole and will make it easier to install panniers or buckets. Check out my other instructables to carry more cargo on your bike!