Be a Catholic
If you're already Catholic, congratulations: that's a big hurdle. If you're not baptized yet, get baptized as a Catholic. If you're part of another Christian denomination, join the Catholic Church. That may be the easy part on your path to official sainthood. Tha's not to say that people of other faiths can't achieve holiness; but for canonization in the Catholic Church, you have to be Catholic.
Now comes the hard part: live a holy Christian life full of "heroic virtue." In other words, be a real Christian, and not just a person who says he's a Christian but doesn't act like one. Take the Ten Commandments and the Sermon on the Mount (and the rest of the Gospels for that matter) seriously. Be charitable, love your enemies, pray for those who persecute you. Give generously to the poor. Devote your life to God even when it's hard—especially when it's hard. And if you want to increase your chances even more, invite others to join you in doing this. (Starting a religious order is usually a swift path to sainthood.)
By the way, remember that your holiness is a gift from God. You can work hard at it, but ultimately it is a "grace" or a "gift." Don't forget who is in charge. And it's not you.