If you've never kept a sketchbook, now's the time to start.
I never kept one either and over the years, I can't think of but one or two drawings that have survived.
When I decided to actually try to discipline myself to keep a sketch book, I also purchased an inexpensive portfolio and I eventually move my sketches into that book. It surprised me to learn this evening that I have completed almost 25 sketches in the last few weeks. I had no idea!
Many of the sketches are simply "thinking out loud" quick drawings.
Others are like a journal entry which shows what I'm feeling or thinking.
Some are studies of a particular aspect of a project I may be having trouble with.
I used to jot down ideas on any piece of scratch paper I could find, but I have learned that these little snippets of paper never survive. By trying to contain my ideas, whether sketches or a short note to myself, in a sketch book venue, I have found that not only are these ideas more likely to survive, but going back and looking through the drawings is really fun.
So keep a sketch book.
Then share it.
(More sketches later.)