Locate the valve on the inside of your bike's wheel. There should be a cap on it, and you must unscrew it before you can attach the pump. The cap is smaller than a thimble, so put it in a place where you will not lose it. Turn the wheel until the valve is nearest to the floor, not at the side or top of the wheel. If it is a presta valve, you must unscrew the top of the valve after removing the cap.
Attach the pump to the valve. If your pump has two holes, remember that the smaller hole is for presta valves, and the larger hole is for standard valves. Most pumps have a lock switch that you can flip up to fasten the pump once it's on the valve. Do not attempt to put the pump onto the valve if it is already in the locked position. The valve should be as deep into the pump hole as possible. Do not lock the pump until this has been accomplished. Once locked onto the valve, you can begin pumping air into your tires.
Pump up your tires by retracting and compressing the handle. There are various sizes of pumps, some of which are hand-held, others that stand on the ground and can be stabilized by standing on. If your pump does not have a pressure gauge, you must feel the tires with your fingers to make sure you have enough air in them. The tires must be very hard. You should not be able to compress them with your fingertips more than a centimeter.
Unlock the pump and pull it off of the valve. Hold the base of the valve while twisting the pump slightly as you remove it. Replace the caps, and you're ready to ride.
