How do you pump up a bike tire with a skinny valve?

To pump up a bike tire with a skinny valve, you will need a pump that is compatible with a Presta valve. First, unscrew the small nut on the valve to open it. Then, attach the pump nozzle securely to the valve and pump air into the tire until it reaches the recommended pressure level. Finally, screw the nut back onto the valve to close it.