When you fly with Air France you can check in up to 30 hours before departure, which allows you to pick your seat and print out your boarding pass, consuming far less time at the airport desk. At this stage, you can also choose to add extra baggage for a fee.
Most passengers are allowed one item of hand baggage measuring less than 55 x 35 x 25 cm. Checked baggage allowances vary depending on your fare, but all items must be less than 158 cm square, or an extra baggage fee will be levied. The same applies for all bags weighing more than 23 kg.