When you are doing mundane tasks, like washing dishes, that is when many writing ideas come to you. I don’t know why. Maybe it’s because your hands are wet and you are busy and it’s the most inopportune time to write . . . all I know is when this happens, you need to dry your hands, grab your keyboard or writer’s notebook and jot down what you’re thinking about.
This is called gathering ideas. You may not write about every idea you have, but you will have plenty of ideas to write about, if you make a note of them when they occur to you. Washing dishes, vacuuming the floor, sweeping . . . when the muse appears, make note of it.