Hey Tracy!
Usually when I rollerset my hair and after the initial flat-ironing, I try to avoid using additional heat for the duration of the set. What works for me is at night I set my hair in 3 large pin curls to maintain the loose, tousled curly look:
Here are the pin curls:
Also sometimes I'd do 2 pin curls - one on top and one in the middle like in the above pic, but the hair where the 3rd pin curl is - I'd wrap instead.
Here's the result - hair is a bit frizzy because it was beginning to revert. Here my curls are somewhat flipped, but I can use my fingers to have the curls flip or bend - depending on what I'm going for.
HTH!