Depends on what badge you mean.
Some of them are listed here: TeamSpeak Badge List (outdated)
Some are sent to one’s email (Merch Badges, TeamSpeak Jedi, Official Teamspeak Gamer).
Some are auto-assigned (Gamescom and other expos, Addon Creator).
Others are posted on TeamSpeak’s social media accounts (instagram, facebook, twitter).
Note that most of them are only available until some date and no later than that.
