You don’t need to warm your car in the morning unless it’s a very old model.  Don’t idle while waiting to pick someone up, or waiting outside a store.  Avoid using the drive thru. Don’t drive around the parking lot looking for a space; pick the first one and get a little exercise!  When approaching a red light, start coasting so that when it turns green, you are already moving. Combine shopping trips into one. Keep your tires fully inflated and your engine tuned up (if you have one).  

Did you know?  
Vehicle emissions are the leading cause of “ground-level ozone,” an odorless gas that is a severe irritant to your lungs and throat.  In the summer, ozone pollution can be especially bad, and young children and the elderly are most vulnerable. Hospital admissions of children with asthma soar in the summer due to ozone created by vehicle exhausts.
(Environmental Protection Agency and National Institute of Health)