Songwriting suggestion: Write a song with a central message of enthusiasm for some thing, product, place, person, event, or activity.
Where to find ideas: What have you enthused about lately? What have other people raved about to you? What brings joy into your life?
Tip: Write the chorus so it could pass as a commercial on radio or TV. The chorus should express the song's central idea in full, even without the help of the verses.
Here's the secret: Zoom in. Don't try to cover your whole subject. Get more specific. Pick one aspect or angle and make it the central theme (and hook) of your song. When the Beach Boys enthused about the girls they met in their travels, the chorus could have been "There are terrific girls everywhere you go." What they actually sang was more specific, and much better: "I wish they all could be California girls."