You should wash your hair as often as every 2 to days or at least once per week.
Unless your hair is dirty you want to avoid washing your hair everyday as washing your hair everyday can lead to dry hair, dry scalp and possible hair loss.
Dry/damaged hair: Every 5-7 days to allow some of your hair's natural oils to be retained on the scalp.
Fine/thin hair: Every other day to provide your hair with enough moisture.
Wavy/curly hair: Every 4-5 days, depending on the density of your hair.
Coiled hair: Once a week for optimal hair growth.
Washing the hair less often can help the scalp remain healthy, prevent itching and flaking, and keep the hair soft and shiny.
People with very oily scalps may develop acne on the scalp or along the hairline and may need to wash their hair more frequently to keep their hair looking clean.
Odors build up easier in thicker hair, too, making it key to really dig and clean the scalp during washings.
Prolonged periods of not washing can cause cause buildup on the scalp, damaging hair and even impeding its ability to grow.
Signs that it's time to wash your hair include.
You're Experiencing Product Build-Up.
Product buildup is a reality and it will come for you if you're not washing your hair enough.
Your Hair Feels Oily.
Your Hair is a Tangled Mess.
Your Hair Texture is “Off”.
Your Hair Doesn't Smell like Your Wash Duo Anymore.
Oil your hair no more than 1 to 2 times a week.
Leave it on for approximately an hour or two but you don't need to leave it on longer than that.
When you leave oil on too long you run the risk of zits because oil will run down onto your skin and you also don't add any real benefit by leaving it on longer.