1. Make sure your OBS version is up to date (at least v28 or higher)
2. In OBS, go to Tools -> WebSocket Server Settings
3. Enable WebSocket Server and Authentication
4. Set a Server Passsword you will remember and hit apply and OK.
5. Create a channel point reward on Twitch.
5. Go to the generator and log in with Twitch, then fill in the rest of the details and hit generate.
6. Copy the URL it gives you and create a new Browser source with the URL in OBS.
7. Everything should work, try it out!