if im at the mall or a busy store and ill be gone for a while .... i will park at the back of the parking lot and usually back into two spots.... right downt he middle line of the two and this usually works. I only have one door ding on my car as of yet (*knocks on wood*)

where i work i can see a piggly wiggly parking lot and i kid you not those shopping carts can get up to bout 20mph. I will back in between two straight cars and get my passenger side super close to their passenger side. So my massive door doesn't hit the car next to me.

and if they have a passenger, well then tough

I bring a padded car cover with me where ever I go.

And that's how you ensure you'll get door dings.

I don't sweat it much. If your car is a DD then it's gonna get beat up. No sense stressing over it. All it will do is bring you ill health.