You must revert your existing Development environment, or create and set a new Development environment, to the Waveset application baseline that corresponds to your Production environment. You must also reset the platform in your Development environment to match the platform in your Production environment. For more information, see Step 1: Document Your Platform.
Use source-control tools to manage your configuration settings, any custom configuration objects, any custom code, test plans, and automated tests. For more information, see Source Control and CBE.
If your site’s processes allow administrators to change Waveset configurations and customizations directly in the Production environment (for example, without updating the baseline version in source control), then you must compare the current production configurations and customizations to those in the source-control baseline. Identify any changes in the Production environment, apply each change to the Development environment, and retest as appropriate. Merge these changes into the source-control baseline for your Waveset application. If the production changes seem significant and cannot be fully tested in the Development environment, consider promoting the updated Waveset baseline to the Test environment and retesting that baseline before proceeding with the Waveset upgrade.