I've been carrying enough smaller denomination bills and coins so that I can provide exact change, or say no thank you to the coins they offer in change.

The biggest hurdle is pre-paying for gasoline. I just signed up for a gasonline credit card (rather than using my main credit card as there is a much higher chance of my card getting skimmed at a pump; it happened to me a couple of times before I went cash-only).

At least with the fuel card, I will get the same discount as I did when paying cash. I also have a box of gloves in my vehicle to handle the fuel pump with.