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

paid action
A video website card is used in a promoted tweet to encourage users to visit your website.

You need this to get it done:

Tweet Text
Text to accompany the video card and website link (maximum of 280 characters.)
The headline appears under the video and briefly describes the product/service which you are advertising (maximum of 70 characters, recommended no more than 50 to prevent truncation.)
File format: .mp4/.mov
Aspect ratio: 16:9 or 1:1
Maximum file size: 1GB
Video codec: h.264, baseline, 4:2:0 colour space.
Frame rate: 29.97fps or 30fps (frames per second)
Recommended bitrate: 6,000Kbps - 10,000Kbps (for 1080p) 5,000Kbps - 8,000Kbps (for 720p)
The URL you would like to send your audience to (must begin with http:// or https://)
Requirements missing or found errors? Report

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

Twitter Business - Advertiser creative specifications
Official information on creative specs for ads.
Link missing here or found errors? Improve How-Tos