The Google Tag Manager plugin adds a field to the existing General Settings page for the ID and outputs the javascript to make it work.
You can sign up for a Google Tag Manager account here.
This plugin makes it even easier to use Google Tag Manager, adding all the code itself — all you need to do is provide the Account ID!
google-tag-manager.php
to the /wp-content/plugins/
directorySettings
> General
and set the ID from your Google Tag Manager account.Two possibilities: First, you haven’t yet specified the ID in the admin panel, or second, your theme is missing a <?php wp_footer(); ?>
call.
wp_body_open
hook in core.