The plugin registers your copyright with Numly and returns the Numly Number (ESN), barcode, and verification links to your blog post automatically.

Noted That:

To install correctly this numly-numbers.zip.
Fisrt Download the numly-numbers.zip to your computer
Extract/Open numly-numbers.zip to Your Computer.
Then, Find readme.txt file inside numly-numbers.zip and Open readme.txt.
Now, Read the Requirements of this plugin. Which Wordpress Version and PHP Version are required to run this Plugin in Your Wordpress Site.
Then, Follow the the Tips Below.

Start the Tips:

1. First Download "numly-numbers.zip" Plugin to your Local Computer. (Click Download)

2. Then, Login to your "yourdomain.com/wp-admin" Dashboard.

3. Then, Click on "Plugins" + "Add New" from left sidemenu of Dashboard.

4. Now, Click on "Upload Plugin" button.

5. Now, Browse "numly-numbers.zip" Downloaded plugin from your computer, Where you downloaded numly-numbers.zip According to Step – 1 Above then, click on "Install Now"

6. Now, Click on "Active Plugin"

7. Then, See left sidemenu. "numly Numbers" folder is added on left sidemenu. Now, Click on "numly Numbers" folder.

Noted that: If you do not see "numly Numbers" folder on left sidemenu then, see at left sidemenu "Settings" or "Tools".

8. Now you configure yourself oR Watch video tutorial below about numly Numbers Configurtions and Settings or How to work "numly Numbers" in your WordPress site.

After Activated Plugin According to Step-6 then,

Go to "Plugins" + "Installed Plugin" from Wordpress Admin Panel Leftside Menu.
or Direct go to: https://yourdomain/wp-admin/plugins.php
Then, Find "numly Numbers" Activated Plugin from Plugin List.
Then, Click on "Settings" from Plugin that is numly Numbers
Now, Edit/Add/Config the setting and Click on "Save Changes" button,

Guide

Guide
Copy the entire folder numly-numbers/ into wp-content/plugins/ folder on your blog. Activate the plugin by going to your blog’s Plugin tab and clicking Activate. Then go to the Settings menu and you’ll see numly numbers listed. Enter your numly username, chose the license you want to use, and whether you want to show the barcode or not. Some where in the post loop such as in the single.php page paste the following where you want it to show `ESN Copyright:'); numly_output($id); ?>`

Copy the entire folder numly-numbers/ into wp-content/plugins/ folder on your blog.
Activate the plugin by going to your blog’s Plugin tab and clicking Activate.
Then go to the Settings menu and you’ll see numly numbers listed. Enter your numly username,
chose the license you want to use, and whether you want to show the barcode or not.
Some where in the post loop such as in the single.php page paste the following where you want it
to show ESN Copyright:'); numly_output($id); ?>

your, numly, blog, links, post, automatically, verification, number, registers, copyright,

Name
How to add Spiff 3d Product Customizer in Wordpress
How to add Screen Snow in Wordpress
How to add Stage Wp Plugin Manager in Wordpress
How to add Ag Twitter in Wordpress
How to add Tiny Search Replace in Wordpress

Reffered: https://wordpress.org/