Run errands "on the way." This can be on the way to work, on the way to lunch, on the way home or on the way to wherever. Try to group your stops so you can take care of as many things as possible in one trip.
You can streamline your visits to the doctor or dentist too. Schedule all your kids' appointments back to back, so you're driving there and back only once.
The phone and Internet are great timesavers. Call stores or browse their Web sites to make sure they have what you want before you venture out. You can order postage stamps and prescription drugs online too. And why waste time waiting for a haircut when you could be doing other things? Call ahead to see if your salon is running on time.