Itchy scalp is a big disorder, but you can prevent and treat this problem From these following home remedies.
Apple cider vinegar
Add apple cider vinegar to last rinsing water to get rid of itchy scalp. Rinse your scalp with this water and do this remedy daily for the best results.
Apply Lemon juice directly to the scalp. wait for 20 mins then rinse your scalp with water.
Tea tree oil
Add 10-20 drops of tea tree oil to baby shampoo and use this mixture to wash your scalp daily until you get the better condition of your scalp.