Hiya HTHUTCH,
Mike and I both use different methods, he tends to stick with the same atty, and add whatever he feels like to the same one. I tend to swap around, blackcurrant/American Red Tobacco/apple etc, all different atty's and carts.
I leave the carts on the attys when not in use, but for some reason have a habbit of pulling the cart away from the atty slightly

Happy vaping
Ellen