Conditioner doesn’t have the ability to turn naturally straight hair curly but, conditioner-only washing has been known to encourage more of a curl to develop in hair that has a natural inclination to curl, like loose wavy hair for example.
Conditioner-only washing is a great way to refresh your hair between washes without drying it out too much.
Hair that doesn’t have enough moisture is much harder to control and is often more frizzy than curly. So, by avoiding shampoo and washing with conditioner only will give your hair more moisture, making it much easier to control and curl nicely.