Use a funnel and put it into the filler tube on the engine and only add what is needed.the filler tube will usually have a bright yellow lockable cap that has transmission formed right into the cap on it..just remove the cap/dipstick and place the funnel in the tube and add the fluid a pint at one time then recheck with the dipstick for level. If you need more add more then recheck. Once it is filled to the right level replace the dipstick and lock it down your done.the dipstick will tell you to add or not according to the markings on it.