Page Customization 
Most pages in SAP Sourcing are composed of a vertically arranged list of fields and dividers between fields. While fields and dividers have different features, the mechanisms for customizing them for the user interface (UI) are identical.
You can customize page elements in a variety of ways, including the following:
Change a field label
Make a field editable or read-only
Hide a field
Make a field required
Add a field description
Change a field position
Rename a tab
This section describes how to customize a page element.
The procedure for customizing a page element consists of the following steps:
Locate the page UI metadata in the Reference Guide. The Reference Guide contains the metadata for each page in the SAP Sourcing application.
Create a page customization and add an element override.
Optionally, apply conditional page customizations.
Test your changes.
After saving the page customization, you can test your changes by navigating to the customized page.
For detailed procedures, see Customizing a Page Element.