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

paid action
Create a video ad to appear on user's Instagram feeds.

You need this to get it done:

Facebook Page
Instagram uses the same advertising tools as Facebook, so a Facebook page is required in order to use the Ads Manager.
Instagram Business Profile
An Instagram Business profile is required in order to be able to run ads on Instagram.
Maximum file size: 4GB
File format: Most supported, but h.264 encoding recommended with square pixels and fixed frame rate.
Maximum video length: 120 seconds
Minimum video width: 500 pixels
Video aspect ratio: 1.91:1 to 4:5 (1% tolerance)
Captions: Supported
Audio: Optional (stereo AAC audio compression at 128+ kbps)
A short caption can be added to your ad (maximum of 90 characters.)
Marketing Objective
The following objectives are compatible with Instagram Feed Video Ads:
App Installs
Brand Awareness
Lead Generation
Store Traffic
Video Views
The link you wish to include in your ad (where you would like to send your audience to.)
Call to Action
The following calls to action are compatible with Instagram Feed Video Ads:
Apply Now
Book Now
Call Now
Contact Us
Get Directions
Get Showtimes
Get Quote
Learn More
Listen Now
Request Time
See Menu
Send Message
Shop Now
Sign Up
Watch More
Target Audience
Choose the target audience for your ad (gender, age, location, interests, etc.)
Duration and Budget
Choose how long you want your ad to run and what your budget is.
Choose currency, enter payment details and pay.
Requirements missing or found errors? Report

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

Facebook Ads guide - Instagram Feed (Video)
Creative specs and technical requirements for Instagram Video ads.
Link missing here or found errors? Improve How-Tos