Tip: Getting the Updated WSP File using Visual Studio 2010

1. Create SharePoint WebPart and do the necessary things you want.
2. Don't Deploy the WSP.
3. Now right click on Project under the Solution file.
4. Now click on Package.
5. Now you will get the updated WSP file.

Note:-
It's Better you delete the old WSP before clicking package so that you can know the difference.