Lyon Airport is divided into three terminals: 1, 2 and 3. As the airport isn’t big the terminals aren’t far from each other.
One good thing to know is that the terminals run from left to right 2 – 1 – 3, with Terminal 3 being the smallest, newest and farthest away of the three terminals.
There is a sign leading to Terminal 3 and you might have to walk down an outdoor passageway to get to the terminal.