There are many ways to hitch up your 5er. You just need to find what works for you. And as always practice makes perfect. This is what works for me.
First I placed a strip of yellow tape on the pin box and a strip on the underside of my tri-fold tonneau cover. This is what I see in my rear view mirror. Just need to of course line the two up.
For the correct height I installed a Hoppy Level Plus. You just need to remember to adjust the smaller level before you unhitch. When it is time to hitch up, just return the 5er to the preset level.
This works for me. I can easily hitch up by myself. But alot of times I will let the wife back the truck up while I watch. She is actually getting pretty good at it.
Good luck, John