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

Requirements
You need this to get it done:

Cover Video
Collections require either a cover image or a cover video (but not both.) The cover image/photo is the highlight of the post and is what draws in the viewer's attention before looking at the products listed below it.
Cover Image
Collections require either a cover image or a cover video (but not both.) The cover image/photo is the highlight of the post and is what draws in the viewer's attention before looking at the products listed below it.
Product Images
Images of the products that you wish to advertise in your post (minimum of four.)
URL
The link you wish to include in your post (where you would like to send your audience to.)
Template
Choose a template for your collection.
Payment
Choose currency, enter payment details and pay.
Headline
A short headline to grab the audience's attention and briefly explain what your ad is about (25 characters recommended.)
Duration and Budget
Choose how long you want your ad to run and what your daily budget is.
Text
A short description to accompany your image (90 characters recommended.)
Requirements missing or found errors? Report

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

0
Facebook Ads Guide - Collection (Facebook feed)
Specifications and requirements.
Official
0
Facebook Ads Help Centre - Create a collection ad
Step-by-step guide on how to create a collection ad.
Official
Link missing here or found errors? Improve How-Tos