It's hard for me. I drive a lot, it seems like there's always doctor appointments or dentist appointments or I have to meet with a client etc etc.
I try to group trips, but with a 2 yr old and a 5 month old, that doesn't work out so well. Getting them in and out of the car multiple times makes it take at least twice as long, not to mention having to nurse the baby randomly, the two year old often falls apart after just 2 errands, on a 5 errand trip. It's rare that I can leave them at home.
Keeping up with maintainence like making sure tires are inflated, fluids are all full, that's stuff my dad, a mechanic, wouldn't let me forget.
One thing I do though is keep up with loyalty points. I have a Speedway card, I get points per gallon of gas. They also give bonus points. These can then be used to get coupons for gas discounts. I will often buy a gift card, get bonus points for that, then use that gift card to pay for my gas and get bonus points for that, and sometimes, even use the coupon for like 10c off a gallon (or whatever it is)