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

Do a live broadcast to your audience using LinkedIn Live.

You need this to get it done:

Streaming Tool
Choose a streaming tool which best suits your requirements. See how-to articles for a full list of third-party LinkedIn Live broadcast partners, as well as technical documentation and set-up information for each one.
Encoder Settings (Cloud Services)
If you are using a cloud service to stream, here are the encoder settings you should use:
Duration: Up to 4 hours
Aspect ratio: 16:9
Resolution: Up to 1080p (ingress) or up to 720p (egress)
Frame rate: Up to 30fps
Key frame: Every 2 seconds (60 frames)
Bitrate: Maximum 6 mbps video, maximum 128 kbps audio, 48 KHz sample rate (ingress) or 3.5 mbps (egress)
Encoding: .h264 video and .aac audio
Protocol RTMP/RTMPS (ingress) or adaptive bitrate (egress)
Requirements missing or found errors? Report

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

LinkedIn Help - LinkedIn Live Video Broadcasting FAQ
Frequently asked questions about broadcasting using LinkedIn Live.
LinkedIn Live | Getting Started
How to get started with LinkedIn Live (how to select a streaming tool, integrate your tool with LinkedIn and then go live.) Also lists important guidelines to follow.
LinkedIn Help - Broadcast with the LinkedIn Live Feature
Guidelines and best practices for streaming content, list of third-party broadcast tools, troubleshooting and encoder settings for broadcasters using cloud services.
LinkedIn Live | Best Practices
Best streaming practices and tips and how to measure your success.
Link missing here or found errors? Improve How-Tos