Toastr is one of those GUI items everybody is familiar with. It is the standard in feedback on webpages. Adding this to your solution is almost mandatory.
After installation of the nuget you’ll need to include the js and css files in the _layout.cshtml razor page. Now add some helper classes like the MVC Wrapper for Toastr from Johan Ohlin. This makes creating and showing the Toastr messages really easy by extending the Controller.