See the Fuel!!
Always, always, SEE the fuel before flight! Either by looking into the tank, looking through a sight window, by dipping the tank with a small diameter tube, or by dipping the tank with an unpainted wooden stick. Never assume. Two people were killed some years ago when staying overnight on the way to a flyin. They filled the tanks in the evening to allow an early start next morning & unfortunately must have ASSUMED the fuel was still in the tanks. It wasn't, it had been stolen & the engine stopped shortly after takeoff. Very sad. DEAN.....