Definitely check in on line as early as possible, usually 24 hours before the flight. This will give you a "better spot in line" in case the flight is oversold, etc.
You may not be able to get a boarding pass at home as the airline may want to physically verify your passport and other paperwork. Don't worry about that, you'll be at the airport in plenty of time for the agents to take care of it.
Have a great trip!