In channel admin, open the League Claims tab and claim the league. It lists every league that doesn't have a broadcaster yet. The league's owner gets a notification and can accept or decline.
Once accepted:
- your channel's badge appears on the league page
- its races flow into your schedule
- the channel owner gets full admin rights on that league
If you own the league yourself, it attaches straight away. A league with no owner can only be attached by the GridCast team — ask in Discord.