Know your usable fuel tank size, install an hour meter, calculate your burn rate (GPH), and keep a log of hours at every fill up. If you know the hours you have ran since the last fill up and your average burn rate you can calculate how much fuel you have used and how much fuel you have left. It is very accurate and useful when calculating range. After a little practice a look at the hour meter will give you available fuel. A stick is accurate but hardly easy to do when underway. More accurate than a fuel gauge. Hour meters are inexpensive and serve to keep maintenance schedules, trip logs and other purposes.