Dream catchers are meant to catch all the bad dreams/spirits that comeyou're way. Most people who wear henna's are quite spiritual & believe that if they wear it on them,no bad spirits will come near them.
Most of the women on their wedding day, demand Arabic mehndi design on their hands as the patterns on this category of henna designs are attractive and simple yet suitable. Description from pinterest.com. I searched for this on bing.com/images