I drive easy, no abrupt starts / stops, I'm doing the speed limit (or a little less), and no A.C. It's actually kinda fun, I like the challenge.
It's funny how things come around. I was doing the same thing during the first big gas crisis in the 70s. I was 2500 miles from home on a road trip when gas went from $0.43 per gallon (Montana) to over a dollar a gallon on the east coast in something like two weeks. I had about $120 on me and no credit card.
But that 1973 Subaru got 44 mpg without trying, and I pushed her up to 60 mpg on the trip home by driving steadily around 50 mph. It also had a 17 gallon tank if you pushed it to fumes. 1000+ miles a tank (and 20 hours or so of driving per fill up). By the time I got to Nebraska I felt like I could live it up and start buying things like food.
Ever since, even in good times, I mostly practiced what they call hypermiling. I used to get 49 mpg in a Chevy Celebrity on the highway. But on the I5 corridor it's impossible. Speeds range from 5 mph to 70 mph in the space of a few miles. Really wrecks the whole scheme.