After you create your player;
- Start in the Memorial Cup and choose a difficultly you're comfortable at - All Star and Superstar have become much harder in the last 2 years.
- You should get drafted in round 1 or 2 to be safe.
- Make your team out of pre-season by playing the games and getting points.
Now, once you're on the team Simulate every 2-3 games but play the 3rd and get some points. This keeps your EXP high, enough to stay in the lineup. I got sent down once (this might just happen regardless of how well you're doing) but it wasn't long until I was back up in the bigs.
At around the Trade Deadline keep an eye out on how well your team is doing. From here on out you may have to manipulate the wins by sim/save/quitting or if you're lucky, you got drafted to a contender already. If you want to push it, you can try simming from here to the playoffs but make sure you save first.
Once you're in the playoffs, sim/save every time you string together a couple wins. Then, when you're in the 4th Round (Finals) play the Cup clinching game just to be safe. After the game is over you should unlock it once your GM sends you a message/notification saying how proud he is, etc.