If you dident want to use parking mode at all, you would not have needed the dedicated hard wire / parking mode kit, then you could have made do with the supplied PSU hardwired to a single fuse.
BUT ! if you want to be able to use the parking mode once in a while, then as i understand it now all you can do is active power off the camera like jokiin explain ( it will come on automatic when you get back to your car and drive off )
Alternative you could use a short timer value like i plan to do when i get the HW kit, so i will just use 30 minutes - 1 hour as that cover all my parking when shopping, and at home i don't need parking mode as i have CCTV on the car.
So my plan is to if i should need longer parking mode coverage 1 - 2 times every year, then on those occasions i would just up the cut off timer from the short time i would always use to say 6 hours for a movie and dinner with some imaginary babe.