Save fuel with super unleaded
Not only by a different driving style can save fuel. It is much more obvious to first think about which fuel you are using.
Some cars can be converted in a few steps and without technical understanding to super unleaded. Of course, the liter price is higher, but most of the time the consumption decreases, while at the same time the performance increases. At different Opel models one finds in the engine compartment top right a plug on the "91" or "95" stands. If "95" is seen, the engine is already set to super-lead-free. To adjust, turn the plug upwards out of the holder, then pull the two holders back and remove the cap. Then turn it over so that the desired number (91 = normal, 95 = super) is up and plug in again. Put the whole thing back in the holder and the engine electronics are set to the other fuel.
For cars that do not have this plug, you can usually change the electronics in the workshop. Afterwards just test how the consumption is now. Reset on normal gasoline is possible in the same way.
When switching from normal to super empty the tank as far as possible and make full afterwards as possible with super. Before switching the electronics, run the engine for a few minutes to consume the remains in the fuel line. So you can avoid damage. When switching from super to normal this does not have to be considered.
And: refueling with super unleaded gasoline only brings benefits if the electronics are set to super. If the setting is left on normal petrol, there are no benefits to notice.
PS: There are also cars that contain sensors that automatically detect which petrol is fueled. The motor then automatically reverses.