1. Log in to your WordPress Dashboard: www.yoursite.com/wp-admin
2. Go to Plugins, and click Add New.
3. Search for Disable Comments
4. Locate the Disable Comments plugin, and click Install Now.
4. Click Activate Plugin.
5. After activating the plugin, click Plugins at the dashboard on the left.
6. Look for the Disable Comments plugin in the list of installed plugins, and click its Settings.
7. Choose how you want the comments to be disabled; Everywhere or On certain post types.
8. Click Save Changes.