You guys are getting within a day of each other! How fun!
The salon is usually very good if you bring a lot of pictures and patience. Makeup, you'll probably want to do your own though if you're a makeup artist. I don't think you'll be happy otherwise. Or have a friend do it?
You used to be able to bring in external hairdressers and makeup artists for the cost of a daypass (I recommend MVP), but I don't think they allow it any more. It's worth asking, for sure!
As for decorations, they provide white. Any color you want will be extra.
The only comment I can make on what to bring or not bring, is don't waste your time, money, or suitcase on candles. Outside it's too windy to keep them lit and inside they just aren't needed.