Add link here to setting up tag manager in google omnivore article etc
The first step is made in your Google Tag Manager account
Log in to your Google Tag Manager account at https://tagmanager.google.com/#/home
Click the Cog shape to the top right of your relevant Tag Manager instance

Click Install Google Tag Manager

Keep this window open while completing the Shopify steps as this is a two step process.
Copy the code in the top box using the copy icon on the right

The second step is made in your Shopify Admin
Log into your Shopify admin
Navigate to Online store -> Themes

In the theme drop-down, click Edit Code

Open your theme.liquid file

Paste the first code snippet you have copied from Google Tag Manager (labelled as step 1 in the instructions above) as high in the <head> of the theme.liquid code as possible.

Now go back to Google Tag Manager and copy the code labelled as step 2
Paste the code snippet as high in the <body> of the theme.liquid page as possible.

In your Shopify admin, click Save.
How to check if GTM code is present on your website
The easiest way to verify that Google Tag Manager code is present on your website is to check the source code of your Shopify store frontend.
On the homepage of your website right click -> view page source and search for “Google Tag Manager.” If Google Tag Manager has been added successfully, you will see code similar to this:
