I use warm water to wash my hair, after putting on my conditioner I rinse with cold water. My hair initially didn't like being rinsed with cold water. My hair would get really hard, and as a result became very difficult to detangle. I stopped doing it for a while, then I started to wash in twists, and I decided to revisit cold water rinses. My hair loves it. I've noticed a difference in my hair, it looks shinier, smoother, and feels more moisturized after I do a cold water rinse. My hair still gets hard initially after doing the cold water rinse, but if I let my hair air dry for 10 minutes or towel blot my hair the hard effects go away and my hair softens up. I think the cold water puts my hair in shock and it needs some time to warm up again, but the beautifying effects still remain.