For product variations Rey theme uses WooCommerce Variation Swatches plugin which is the best free plugin for this sort of need. I tested over 10 free and commercial plugins and this one seems to be the most fastest, clean and feature rich amongst all.
To install this plugin simply head over to Appearance > Install plugins and you should find it listed there. Read more about installing Rey plugins.
I won’t explain how to create variable products and add product variations because there are literally a ton of articles & videos online on how to do it:
- https://docs.woocommerce.com/document/variable-product/ (Official docs)
And also tutorial on how to add variation swatches with WooCommerce Variation Swatches plugin:
This plugin WooCommerce Variation Swatches is packed with this feature in its PRO version, so i have developed an alternative for displaying product variation swatches in the product listing.
Access Customizer > WooCommerce > Product catalog > Components and loo for Variation Attributes section of options eg:
In the Attributes type please select the attribute type to show and its position.
Here’s an example with colors swatches: