dog doors and training dogs to use them.

I finally got a dog door for my 5 beasts. Im so happy! All 4 cats have figured out to use it on their own with no help, and only one dog goes in and out without me having to hold the flap up. They all go through the door when im calling their names and holding the flap up for them, but how do i get them to do it on their own and how do i teach them that they can come and go as they please?

I've never had a dog door before, my dogs are all use to me letting them outside, so i hope i can get them going in and out on their own. Any tips?

Thanks

 

with luther, in munich I had a little door to go to one of the rooms in the basement, I tried different stuff, I took the flap off, but he was always terrified of it. But recently we got a new one and putit in our sliding glass door that goes to the back porch. The first few days, we would call his name and have a treat on one side, he acted like it was torture!
One day I noticed that when I came home, he was on the back porch, now he just sits out there all the time. I think give it some time and they will just pick it up, as long as you have shown them. good luck!