Natural henna should have a strong, earthy scent. Henna paste has a peculiar smell similar to a barnyard or to damp clay. Some people like this odor while other don’t.
To get rid of henna tattoos or to get henna off read this post. This post contains all instructions. http://mehndinhenna.com/how-to-remove-mehndi-or-henna-tattoo/
To make henna paste / ink or to find the best henna ink recipe please check this post. It contains step by step instructions. http://mehndinhenna.com/how-to-make-henna-or-mehndi/