Optimzely is a popular web optimization tool. You'll integrate Optimzely into your storefront by adding their script to the head section of the page.

So, to integrate this into the storefront you'll edit the "document_top.vm" template in the templates section of your storefront host.

Navigate:

1. Where are the templates located
   
   

   Open

   

2. Select a template to edit. You can edit the templates by directly navigating to the templates:
   
   

   Open

   

     3. Edit the "document_top.vm" template and place the Optimizely code within the head tags.

Open

https://help.optimizely.com/hc/en-us/articles/200904580-Frequently-Asked-Questions