I'm not sure pre-treatment will be as important as post-treatment. But in both circumstances I think it is important that your hair has a strong protein foundation and you also want to make sure your ends are sealed. Find treatments and conditioners with a good protein source in them. For example Nexxus emergencee, sizta2sizta halt breakage control treatment, or even Aubrey's GPB are good treatments. I used to use Fermodyl every now in then when I colored my hair. Good rich leave-ins that I like are Elucence MBC and Paul Mitchell The Conditioner.
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