Registration for physical and remote presence is now closed.
TCL runs the public transport system in Lyon with buses, trams, and metro lines. It works well.
If you are arriving by train:
If you are arriving at the airport:
There are vending machines for TCL tickets at every metro station and nearly every tram stop, and you can buy single fares in a bus. Validate your ticket when you enter the bus, tram, or metro, after which you can use the ticket for one hour on the whole network. It's probably best to buy a bunch in one go, as you might be taking the public transport several times while in Lyon.
If this is your first time in Lyon and you're wondering where to stay, these might interest you or provide a point of comparison (from closer to further away from the venue):