Dreaming of applying henna on feet is a good dream as per dream meaning and interpretation. It means that you will find love and there will be progress in romantic matters. If while applying henna it goes wrong or bad then it means there will be break up or you will be miserable in a bad relationship.
Dreaming of someone else applying henna means that you are not in a good relationship and that you will be cheated.
Dream of all family members or friends putting henna means there will happy occasions in the family including wedding.
A dream to have a meaning it has to happen naturally and not due to any daytime incident influence. If you were thinking about your henna or talking about and then having a dream about it then it has no value.