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

Bounty Board
paid action
Bounty Board is a fast, convenient way to partner with thousands of popular Twitch streamers.

Requirements
You need this to get it done:

Banner File Specs
Dimensions: 600 x 800 pixels
File Format: .jpg/.png
Banner Tracking
Third Party Tracking: 1x1 impression tracking pixels (non-redirecting)
Trackable Events: Start, 30 second view, 2 minute View
Accepted Vendors: DCM/Sizmek
SSL Compliance
Twitch requires all ads and 3rd party vendors to be SSL compliant. All components of video and display ads including creative and tracking must be able to serve via SSL (https).
Requirements missing or found errors? Report

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

1
Twitch Advertising - Bounty Board
Twitch official guide for the Bounty Board.
Official
Link missing here or found errors? Improve How-Tos