Test and publish designs
Once you have completed your design, you can test and publish your customized designs.
On the "Edit payment pages" tab, click the "Publish" tab.
By default, any changes you have made are automatically saved to the design environment.
To publish your design to the test environment (Sandbox), click Promote.
Your changes will be available in Sandbox for testing after approximately five minutes.
Note: Use the sandbox environment to validate the look and feel and page functionality. Only after you are satisfied with your testing should you promote the changes to production.
To publish your customizations to the production environment, click "Promote". Your changes will be available in production shortly.
Your changes are now live.