Wanted! New Material
I don't know about you, but I'd rather be writing than six feet under! All our experiences, whether mundane or magnificent, are fodder for the next story or book or character. They give us something new to write about.
I keep my phone nearby all the time. Who doesn't these days? I use it to jot down ideas when something or someone interesting happens across my path.
Sometimes it's a description; sometimes it's a story idea; sometimes it's a memory. If you don't already, I'd advise you to do something similar. No matter how hard I determine to remember a thought worth noting, I inevitably forget if I wait until I get home or to finish what I'm doing.
David Brin said it a bit differently, "If you have other things in your life—family, friends, good productive day work—these can interact with your writing and the sum will be all the richer."
It's just a twist on the same thought. People say, "Write what you know." Well, between your imagination and research, you can right about much, much more. However, if you've been accumulating characters, descriptions, and story bits along the way, you'll be ahead of the game.
It requires observation. Learn to really see the environment and the people around you. If you pay attention, you may be surprised at how full of ideas your everyday world is.
Do you hear the different sounds feet make as they walk through a mall? There's the quick click-click-click of the lady in spike heels taking small steps. There's the flap-flap-flap of the teenager in flip-flops meandering the walkways. And the slow step-step-thunk of the old man with a cane.
Discipline yourself to pay attention. Make it an exercise. Sitting at the food court some day, just take the time to write descriptions of what you see, hear, and smell. Your writing will improve if you're careful enough to use good, descriptive adjectives.
Wright is right! All our experiences, no matter how dramatic or prosaic, offer us fresh material if we're just open to receive it and fully take it in.