What do you think is the most important thing needed to get a great flex rod set?Great question. I've only been doing flexi rod sets for a year and some change but I've noticed a couple things are essential (for me at least) for a great set.
Start with damp or wet hair. Hair must be pretty damp/wet before setting it on the rods. Setting hair that is near drying will not produce well defined curls. Just as hair must be wet doing roller sets, I've learned that I get the best curls when my hair is wet (but I don't mean dripping wet) or very damp before I set it on rods. If my hair is too dry by the time I reach a section, I mist it with water or Paul Mitchell Awapuhi Moisture Mist before setting my hair.
 Tension is key. Just as hair must be taut when rolled onto a magnetic or mesh rollers, hairiest also be taut when setting it on flexi rods. Because of their "bendy-ness," it might take a while to get the hang of bending the rods into a position that keeps the hair as taut as possible while it dries but it's worth getting the hand off. Keeping the hair taut as it dries prevents puffy roots and frizz.
Nix heavy or oily products. Use products that will not weigh your hair down. You want your curls to be as bouncy as possible so try to avoid products you know are on the heavier side. I try to avoid products I know will not sink into my hair as theses products will sit on the surface of my hair.
 Moisture-prep reigns supreme. I've found that prepping my hair during my wash day with products I know will provide lasting moisture helps prevent dry hair during the week, which in turn cuts down on how often I have to moisturize and seal during the week, which then helps me preserve my curls even longer because I am not manipulating them when moisturizing and not weighing them down with product. With my most recent flexi rod set I think I found my perfect combo of products for super moisturized curls because I didn't moisturize once while wearing my curls (6 days span): I pre-pooed with L'Oreal Total Repair 5 Restoring Conditioner, co-washed with Carol's Daughter Hair Milk Cleansing Conditioner, deep conditioned with Hairveda Sitrinillah Deep Conditioner, and for leave-in conditioner I used Kurlee Belle Thirsty Kurls Leave-In. I've also achieved long last moisturizing curls after deep conditioning with Kurlee Belle Banana Nut & Avocado Deep Treatment.
Stretched roots via two strands twists make a world of difference. I couple sets ago I started twisted my roots by starting a two strand twist before setting my hair on the flexi rods. I picked this technique up from KinkyKurlyQueen (her video is posted here) and I'm so happy I did. Starting a two strand twist helps stretch and blend my 6+ inches worth of new growth with the curls for more uniform results. Starting a two strand twist also makes it easy to separate my curls with easy and without frizz.
• • •My most recent flexi rod set was definitely my softest, longest last set to date (lasting 6 days before I washed my hair) and I used the "essentials" posted above for this set. Even after finger-coming the heck outta my curls, they didn't want to kick the bucket.
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