Our town's in a hollow surrounded by mountain ridges, lotsa hills.Not really a whole lot you can do. The biggest change would icome from how you drive. Less sudden stops and more rolling to the stop, speed limits, gradual excelleration. Some people claim that by over inflating you tires you'll have less tire & road contact thus save gas. Technically this is true and a little over inflation doesn't hurt anything but I have no idea how much over it should be and too much is not good. Also, if you put your car into nutral while at a stop or rolling to a stop you'll lower your RPMs. Again, technically true.
I don't know how much any of that actually helps. I'm sure you'll probably see some differences if you implement all of that but for the most part all these tricks and gizmos don't do much. The type of car you have is what will dictate your MPG. The best thing to do is keep it in good running condition and drive calmly, the lower the RPM the better the MPG.
Another thing that effects your MPG is how and where your city is built. If you have a lot of hills there isn't much you can do about that.
This is why I got rid of my truck a decade ago. Economical cars from there on out. I don't tow or haul anything. The last time I moved a sofa was 3 years ago and I rented a van. All in all cost me about $80, which is cheaper than driving a truck for 3 years. We get snow but it's either bad enough that I don't go to work or its not and in the last 3 years of heavy snowfall where we've gotten 6+ inches my Corolla made it home and work without issue.