Casey Neistat tells us to show up every single day.
I think it was Michael Kenna who said, during an interview, that photography is something you have to do every day.
Showing up doesn't mean that we have to shoot every day. There's so much more to photography than using a camera: from developing / editing the images to publishing and promoting them, organizing your work in books, contacting models, agencies or brands, uploading stock images, planning your next trip, even cleaning your gear or posting on Instagram.
The point is: photography has to be in our minds every day, and we should make every day count, even if it's just a little bit.