No The Henna ceremony is held a week or so before the actual wedding. During the ceremony, the hands and feet of the bride and her guests (and, in some communities, the groom as well) are decorated in intricate designs with henna, a red dye made from crushed henna leaves.
No. Henna is an Indian or Hinduism tradition. Mainly used for events.
What to wear to a Jewish ceremony is somewhat dependent as to which sect the individuals belong to. In general, a certain degree of modesty is expected, however, the more religious, the greater that expectation is. If you are invited to a ceremony of some sort, your best option is to contact your host and ask for advice.
The bride wears a wedding gown. In Orthodox communities the gown will cover her up to her collar bone and the sleeves will reach her wrists. In Conservative communities the gown will cover her shoulders. The groom wears a tux or suit. Unless it's a theme wedding, Jewish weddings (at least in North America), are always formal or semi-formal wear.
There is no cloak worn at a bar mitzvah ceremony. If you're referring to the prayer shawl, that's called a 'tallit'.
It depends on the person's origins, for example "If someone were from Orissa, India, henna is strongly ingrained in the culture, thus it would be more acceptable. However, it would be less normalised in other nations where it is not as widespread." Wearing henna is acceptable for Buddhists, however it is not widely used in all Buddhist societies.
Orthodox Jewish brides don't wear two veils. The veil just has to be able to cover her face and hair during the ceremony, the same as most traditional wedding veils. Some Orthodox brides do wear a veil that's more opaque than normal though.
A suit. Some wear a kittel (a white tunic) over the suit, for the chupah ceremony itself.
It is very common for the guests to wear sarees, it is the traditional clothing of much of India. Have a look at this www.saree.com
The answer to this question depends on why a Christian wants to wear a kippah. In the Jewish tradition, Kippahs are worn as a show of respect for God. Christians have different ways of showing respect for God as well. So no, it's not disrespectful for Christians to wear kippahs if they are in a Jewish ceremony or environment. But it may be best to ask the person in charge if it's ok.
A distinguished professor should wear a conservative, yet elegant, go to a ceremony.
the Jewish community had to wear a star.