Pour it into your car's tank. There is so little oil in a half gallon it won't be noticed.

Don: If you use Stabil in a tightly sealed Gas Can you can use the reminants again and again . Otherwise Octane Booster or as CG advised just throw it in your automobile 1/2 Gallon is not going to be noticed .

Use Sta-Bil 'Marine' concentrated (blue) stabilizer in the gas can when you make your 2-cycle mix and it'll be good for at least a year. It will also still protect in the engine after you run it 'dry', which is not really 'dry'. Most 2-cycle oils also have stabilizer included, so check the oil you use for that. You can get a small dispenser bottle (8 oz) of the Sta-Bil, which you'll need, because for a 1-gal can the amount would only be a fraction of an ounce. Always shake the can before dispensing fuel, and visually inspect it before re-filling for any foreign matter or gummy residue. If you want to take it a little further, you can also add 1-oz Marvel Mystery Oil to each gallon of mix. 2-cycles love it, and so do four cycles. BTW, use the Sta-Bil and MMO in your 4-cycle can too. The Marine Sta-Bil contains more additives than the regular Sta-Bil and will keep them running clean and starting easy.