Some of the places that my posters were placed where on doors and of washrooms, large posters were placed on the wall at the end of hallways , and high traffic areas. You can also advertise on the school's radio and the morning announcements. Another thing that I did was I went around talking to people , presenting myself, telling them who I was and the position that I was running for. Try to influence them that you are the one right for the job, but don't over do it, after a while people just want to run away from you. Also, try to remember people's names .
People like to it when they are addressed by there own name.
No matter who you are talking to, be nice and always focus all your attention on the person that you are talking to. I just like to keep a smile on my face. It's a friendly approach when you have a smile on your face. It's easier to talk to you. DON'T promise things that are too out of line, and you should NOT promise things that you can't do.