How should I educate myself so that I can cast informed votes in elections?

I am 25, and I have never voted in any local, state or national election. I think I have good reason for that: I've never been able to educate myself sufficiently on the candidates to be certain of who to vote for. Also, as a marketing student with a passion for advertising and public relations, I don't think I could vote until I'd seen the inside of a campaign team as a member of it, so that I have a personal understanding of the degree to which a candidate presented is real or idealized. I know that such is unrealistic, because I wouldn't know which candidate to work for. Instead of that, what steps could I take to inform myself, without consuming too much time, so that I could vote in the next presidential election?