Different everyday things can sometimes have interesting metaphorical meanings that feel somehow natural as inspiring for songwriting. One thing that has always evoked interesting creative thought for me is the experience of traveling.
You set out towards a destination, and move towards various goals or plans. What happens along the way may be unexpected, and may leave you with food for thought. I found this to be true for me again, while taking several plane and bus trips across the country to handle some business. Of course there are all kinds of ways to look for and find what inspires you, the next time you travel be sure to take a journal and a camera to give yourself a record of how the journey effects what you're thinking and feeling.
In composing music, one thing that proves helpful for most musicians is to have a way to record whatever comes to mind that seems to want to encourage you towards long and deep thinking. Recording a thought by jotting it down, or the visual impression of a moment that caught your attention may be a key in composing music.
Check back soon for examples of how to use this that may be helpful to your work.