Using the air pumps at a local gas station to fill your bike tires can be dangerous, as these machines could fill the tires so quickly that the tires literally explode. Instead, it's wise to use a pump made specifically for bicycles. Schwinn is a company that manufactures several different types of bicycle pumps. Bike pumps can be a little bit confusing if you've never used them before, and you can actually damage your tire if you use the pump incorrectly.
Unscrew the cap from the valve on the bike tire you wish to inflate. If there is a nut on the valve as well, you will need to unscrew it before you attempt to use the Schwinn bicycle pump. Otherwise, you could break the pump.
Put the pump in the "unlocked" position. To do this, you will need to flip the lever found on the side of the Schwinn bicycle pump down so that it is touching the pump.
Place the head of the Schwinn bicycle pump around the valve found on the tire. Push the head into the valve gently so that it fits snug around the entire head of the valve.
Place the pump into the "locked" position. Flip the level mentioned in Step 2 back into the upright position. Once you do this, the head of the Schwinn bicycle pump shouldn't move from the nozzle.
Grab the handles of the Schwinn bike pump and pull the lever up. Then, push down to add air to the bike tire. Continue doing this until you have added the desired amount of air into the tire. Remember that the tires on a bike need to be firm, but there should be a little give.
Put the lever of the Schwinn bicycle pump back in the unlocked position. Remove the nozzle of the pump from the valve. Then, put the cap (and nut if there is one) back on the valve.