How can I get into modelling?

I would love to get into modelling. I'm 15, almost 5'7 tall, and weight about 105 pounds. Do you think I might be able to? If I needed to loose weight I would. I would do anything. I love fashion and modelling with all my heart; my dream is to be in Vogue. I live in Bristol in England, but could travel to London. How do I get started in modelling? It might be a long shot but I don't want to regret never looking into it. How do I become a runway model?