Scape Scape:
Start small, go for municipal politics 1st. It's the closest level of government to the people and frankly the dirtiest and if you want to get immersion in to the workings of the nation that is the best starting point. your next stop would be the local city hall.
I would say not a bad piece of advise. I'm starting out by having applied and been accepted on to the City of Edmonton Youth Council. I'm seventeen and I intend to serve until pretty close to my age limit.
My uncle knows a man who was in Jean Chretien's Prime Minister's Office and he started out by volunteering for the party.
Though I hate the Conservatives, there no sense in not volunteering because your constituency doesn't largely support the party. It's probably at this time when volunteering is most needed by your party. AND DEFINITELY ESTABLISH CONTACTS!!! Networking is an extremely important part of modern politics, unfortunately.
And becoming a lawyer is good advice as well, my cousin Ovide started out being a lawyer, and he became the first elected Chief of all Indians in Canada.