Along with onion, you will need some things which are completely natural. From onion shampoo you can make yourself at home
You can use onion hair mask.

Ayurvedic doctor Shalini Jugran says that sulfur is found in onion which is considered beneficial in the formation of keratin. It improves blood circulation which makes the scalp healthy and reduces hair fall. The antibacterial properties present in it remove dandruff and allergies.

Dr. Jugran tells that you can use onion in many ways for hair, you can make hair mask and onion shampoo at your own home. It prevents hair fall and is also beneficial for those people in whom gray hair has started appearing at an early age.

To make onion home made shampoo, you will need onion along with reetha and shikakai which are natural cleansers and in the old times when there were no shampoos, people used to wash their hair with these.

First of all, take 2 onions and peel them, after that take about 50 grams of reetha and 50 grams of shikakai and wash them thoroughly. Now cut the onion into small pieces and break the reetha and throw out its seeds. Break shikakai into small pieces also.

After doing this, mix these three things in an air tight container, add about two glasses of water and keep it for 12 hours. It would be better if you soak it in the evening and after leaving it like this for the whole night, expose it to sunlight. You have to expose this mixture to sunlight for about 4 to 5 days.

After doing this, you have to take this mixture in a pan and cook it on low flame. After this, filter it and keep it in an air tight container. On any day you want to wash your hair, mix a little onion juice, 1 teaspoon almond oil and aloe vera gel and massage well, leave it for 10 minutes and then wash your hair with this home made onion shampoo, you will see the results within 2 months and you will forget thousands of shampoos and conditioners.