In the black plastic air intake silencer box, you will see a rubber plug. Pull it out. Hold onto the red tube from the spray can and put it in that hole. Leave the engine running, spray the fog into that hole until the motor bogs down. Then shut it off. Take each spark plug out, spray in the hole about 15 seconds. Put the plugs back in. Push the start button for just a second or 2 to crank the motor over. You are now done.