1. Obey all traffic laws; many of these will indirectly help you save fuel
2. If your car has an economy mode, use it
3. Think ahead and avoid intensive braking: gliding down over 15 seconds uses less fuel than keeping power on and braking for the last 5 seconds
4. On flat ground and uphill, where traffic allows, accelerate very slowly (less than 1 mile per hour per second)
5. Downhill, gravity will allow you to accelerate more rapidly and still realize short-term mileage of 35-40 mpg 
6. Without violating traffic laws retain as much speed as possible when turning onto another road ( accelerating from zero requires a lot of fuel )
7. Bank a few miles per hour when going downhill (at higher MPG) so you can siphon them off (by slowly dropping to your average speed) as you are reaching the top of the next hill
8. On flat and slightly downslope routes, use cruise control; it is much more sensitive than you at maintaining low throttle input
9. When are going from flat to a hill, cancel cruise control before it surges to maintain your speed, the few miles per hour that you lose can be regained going down the other side of the hill, where you can reengage cruise
10. Merging on and off  freeways, use the onramp to your advantage --Most onramps are long enough that with a 20 mile per hour head start, your car can be at the speed limit by the time you reach the merge --Exiting a freeway, uphill offramps can be used to absorb speed; so you coast up the ramp and slowly come to a stop

P.S. You can compare fuel economy of different models at https://www.fueleconomy.gov