So a lot of brides and a lot of mothers actually ask me what the mother of the bride's hair should look like.
I would say stick to something very simple and classic. Try not to look old fashioned. I think for most women a really beautiful blowout is enough. I think, especially if you have shorter hair, even kind of chin-length bob hair, I think a beautiful blow-out usually does the trick.
Some other things to consider would be really classic hair styles, like a French twist or a chignon. Also you want to consider what kind of a dress you're going to be wearing. Be sure that the dress and the hair match.
And, as always, try to talk it out with each other and make sure that there are no conflicts between either side. So those are some great mother of the bride hair styles.