It is given to you after you register your application - link is https://www.twitch.tv/kraken/oauth2/clients/new (which for future reference, can be found at the bottom of the Connections page in Twitch Settings.)
It is given to you after you register your application - link is https://www.twitch.tv/kraken/oauth2/clients/new (which for future reference, can be found at the bottom of the Connections page in Twitch Settings.)