Wedding Hairstyles?!

Hey guys! So I found My Dress!!!!! I'm beyond excited about it and I love it sooo much. I thought I wanted a mermaid dress but when I put on the ball gown I fell in love with it. My hair is about shoulder length I'm trying to grow it out for the wedding I have a year!! The dress has a deep V neck and it's sparkly; I plan to wear a tiara on my wedding day. So I have two questions first one any tips on growing your hair out?? Also, when wearing a ball gown should you do an updo or is wearing it down acceptable?? I included a picture of me so you know about how long my hair is