Go to Sales Channels
Click on Online Store
Click on Themes
Click on Actions
Click on Edit Code
Click on Layout
Select the theme.liquid file
Copy the redirect code and paste it just after the <head> tag as shown below
IMPORTANT: Place it just after the opening <head> tag to ensure it processes first and does not get blocked by another script in your page. This will allow the redirect to work as fast as possible.
Our servers respond in 100 to 300 milliseconds so if the script is the first to process in your page, then the redirect will be almost instantaneous.
The redirect script is an asynchronous non blocking script, hence it will process while the rest of your web page loads. This will prevent any increase in page loading time for visitors who don't end up getting redirected.