First of all, you need to understand the whole game, who's the best player in it, how they are doing it! My suggestion would be to start out by getting a job as an intern or assistant to a professional wedding photographer. The main idea is to get a hand full of experience that no university or school can teach. Build your portfolio while interning, some of the good portfolio platforms are Pixpa or format, exclusively for photographers. Build a good network, a good word of mouth marketing will surely help you to attract the potential client.