I probably shouldn't comment too much on flat ironing; I'm still learning. But you might want to check out a video on the comb-chase method. Longhairdontcare has great a great youtube tutorial.
I don't flat iron often, but when I do I this is what works for me: I do an apple cider rinse before conditioning, then I deep condition, apply a teeny bit of Giovanni Direct Leave-In conditioner, let it air dry stretched, blow dry it with an attachment (using Hana shine shield), and flat iron attempting the comb chase method. It's a work in progress, but I get the best results with minimal shedding this way. I used to be wary of blow drying attachments, but they help me get my hair straightish,so I only have to go over it with my flat iron once. I have a Hana Elite and it's the shiz.