At any store that sells boat supplies you can get a oil to gas measuring bottle. Its a clear bottle with all the oil to gas ratios for however many gallons of gas you want. All you need to know is what is the gas to oil ratio for your motor is. With that said it will probably be either 48:1 or 50:1 for your motor. If you put six gallons of gas in your tank then measure the oil out with the bottle for six gallons and put it in your tank. The drive to the ramp will mix it for you. That easy.