Overview
Folksonomy is a module for implementing social tagging in Omeka S.
https://omeka.org/s/modules/Folksonomy/
This article explains how to use this module.
Installation
It can be installed using the standard method, same as other common modules.
Configuration
After installation, the following settings screen is displayed. In particular, by enabling “Allow public to tag,” visitors can perform tagging. Additionally, by enabling “Require approbation for public tags,” an administrator approval workflow can be introduced.

Visitors
A tag registration form like the following is displayed on the item detail screen.

When entering multiple tags, separate them with commas.

After agreeing to the “terms of use” and license, press “Tag it!” An alert like the following is displayed, stating that it will appear after approval.

Administrators
From the “Folksonomy” > “Taggings” page, you can browse the list of taggings.

By clicking the “?” mark, you can toggle between “approve” and “reject.”

Approved tags are displayed on the public page, while rejected tags are not displayed.

Summary
I hope this is helpful for implementing social tagging in Omeka S and as a reference for implementing similar functionality.