It's a whole process actually. He was previously nominated in the 80s and ended up declining to be present for the unveiling so they canned it.
1. a nomination goes in
2. it must accompany an agreement letter from the artist or thier management company
3. nominees are chosen
4. whoever nominated it forks over 30k for the star to be built
5. the star HAS to appear in person for the star to be unveiled