What should be my apparel?

My church has a Journey to Bethlehem play going on in December. I live in Michigan where it is quite chilly. I have to wear white, because I am an angel. My boyfriend is a Shepard,and we are going out to dinner prior to and I want to look nice, but I have to be in all white and dressed for 0°F temperatures with layers. And I do not have a place/time to change. And I also have to come up with a hairdo, I have shoulder length unmanageable hair.What should I wear to get the elegant yet cozy look? And how should I do my hair that’s easy?