Here you can list your custom lobby for people to join.
The NautsLobbyBrowser bot will join the lobby frequently (and leave again within 3 seconds) to verify the existence of the lobby and update playercounts.
In rare occasions the bot can get stuck in the lobby, if it doesn't leave within 20 seconds, it probably never will.. please report when this happens and create a new lobby.
Follow these steps to find the Steam Lobby ID:
For example, here's a sample lobby link:
steam://joinlobby/204300/109775242526593664/76561198052552162/
In this link, 204300 is the App ID of the game "Awesomenauts" and 109775242526593664 is the Lobby ID and 76561198052552162 is the Steam ID of the profile you copied the link from.