Action Details
Requirements and how-to articles for Mixer's action:

Broadcast live gaming footage to your audience.

You need this to get it done:

Stream Feed
Maximum bitrate: 10000 Kbps (shouldn’t use more than 75% of your available upload)
FPS: 60 supported, but more taxing on performance and upload, 30 works fine for most games
Resolution: 720p or 1080p (720p works fine for most games)
Keyframe: Most streamers set this to 1
Stream Title
A brief summary of what you are streaming.
Choose the game which you are playing.
Channel Audience
Set the maturity rating for your stream (General, Teen or Mature.) If a game has not yet been given a rating by the ESRB, the channel must be marked 18+.
Channel Language
The primary language being used in your stream.
Share Text
This is the text that will auto populate when a viewer clicks the "share" button on your channel page.
Requirements missing or found errors? Report

How-To Articles
A list of useful links for you:

Mixer - Stream Settings: The Basics
Official information on stream settings, such as resolution, FPS, bitrate, etc.
Link missing here or found errors? Improve How-Tos