Wolf10 Was real good.
We have had several gas RVs and do again.
I only thing I will add is that a copy of Street Atlas w/GPS can tell you where to start looking for fuel a day or two (or eight) ahead of time. That can save you a lot of grief.
Then with GasBuddy (either the app or the website) you can find where to buy. Like going south on I-75. If you aren't a Costco member, you want Alexis Rd. Always look at state lines. Fuel is cheaper in Indiana than it is in Illinois, and Ohio is cheaper than Michigan. You will get the hang of this.
Next is (as wolf said) use google maps or earth to look at the station chosen. That 5c/gal may not be worth the effort.
It will take a few excursions before this gets comfortable. Don't ever try to hurry. If someone else in front of you is being an inconsiderate jerk, take the time to admire the workmanship.
Matt