Login to your store (your sitename.com/admin)
on the left panel, click Advanced Settings - > Legacy API Settings
click 'Create Legacy API Account'
In another tab or window, login to your pss account.
on the top right, click Settings -> Big Commerce
In order to work correctly, complete all fields.
create a username and copy/paste it into the Username field under Auth
copy the API Path and paste it into Webstore Domain. Be sure to leave out http and it should end in ".com" not "/api/v2".
Shopping Cart Details
Webstore Domain: the URL of your store
URL for missing image logo : optional placeholder image for when a product doesn't have images. Can be your company logo
Username: the username when creating a legacy api
Token: the token for the legacy api
Product Display Settings
The fields may vary due to each store having a different theme.
Dom Injection Location: the top element with the product information.
Dom Injection Method: generally 'Append' will be used.
Product Form Selector : the form element containing the product/add to cart.
Remove Product Form After Load : check this to keep the page cleaner.