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

paid action
Create a collection ad to appear on user's Instagram feeds. Collection ads are useful if you have a catalogue of products to sell.

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.
Product Catalogue (Instant Experience)
A catalogue of items to sell, which is accessed when the user clicks on the ad.
Product Images
Product images to be displayed below the cover image/video.
Cover Image
File format: .jpg/.png
Minimum resolution: 500 x 500 pixels
Aspect ratio: 16:9 to 1:1 (1% tolerance)
Cover Video
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 resolution: 500 x 500 pixels
Aspect ratio: 16:9 to 1:1 (1% tolerance)
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 Collection Ads:
Catalogue Sales
Store Traffic
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 (Collection)
Creative specs and technical requirements for Instagram Collection ads.
Instagram Business - Collection on Instagram
Specs and design recommendations for Collection ads.
Facebook Business - Create a catalogue
How to create a catalogue of items to display in ads on Facebook/Instagram.
Link missing here or found errors? Improve How-Tos