For enhancing hair growth on scalp:

Mix few drops of cinnamon essential oil in olive/coconut oil (base oil) and rub on your scalp every alternate day. Let is remain in your scalp for all the night and wash off in morning. You can do it regularly for about two weeks to see noticeable difference.

If cinnamon essential oil isnt available at your drug/departmental stores, you can also add some cinnamon powder into your hair oil. However, it might spoil your bathroom decor. So, wash off with good amount of water later on!!