Adding and renaming styles in the current QGIS project

Styles can be saved inside QGIS project files (.qgs). In fact, all .qgs files already contain one style named default, which stores all of the style choices you make in the QGIS project. Styles that are added in this way will only exist when the .qgs project is loaded, which can be useful when you want to store a set of styles that are specific to a project inside the .qgs file instead of relying on separate style files.

To add the currently set style options as a new style inside the .qgs file, open the Layer Properties window, go to Style | Add, and provide a name for the style in the New style dialog box. Once added, the new style will appear and be selectable at the bottom of the Style button. Only one style can be active at a time, so checking one style will uncheck all other styles.

To rename a style that's stored in a .qgs file, open the Layer Properties window, make sure that the style you wish to rename is the currently selected style, and then go to Style | Rename Current.