How to get his attention?

I volunteer at an animal shelter and am attracted to another guy who is employed there. He is there every time I volunteer, and I always go in the opposite direction when I see him or look down at the floor. I'm mainly embarrassed because I wear my frumpy jeans, rain jacket, and walking shoes and always have my hair in a sloppy pony. I do this because I am walking dogs for at least two hours in the rainy PNW weather, and I always get dirty. I want to try to get his attention, but I don't know how!