Good marketers have something called a "swipe file." It's a simple yet effective concept.
See a website you think is really effective? Take a screenshot and put it in your swipe file.
See an advertisement with the most persuasive word choices you've ever read? Copy it and put it in the swipe file.
If you haven't gathered, you're "swiping" ideas so you can repurpose them for your own projects later.
This isn't limited to marketing, though.
Any creative can have a swipe file. After all, there are ideas everywhere just waiting to be swiped.
See something compelling? Add it to the swipe file.
Need inspiration? Open up the swipe file.
There is a world of ideas all around you, every day. And they're just waiting to be copied, reshaped, and made your own.
So long as you remember to observe them as you see them and add them to your swipe file.