You won't learn if you don't put yourself out there. You can't walk until you crawl.
I'm not the type to allow myself to be overwhelmed. The way to build a wall is one brick at a time. Don't try to conquer the world at once, do it one country at a time. I have tons of bits of paper stacked away in drawers and boxes. I'm not organized in my notes but I know where the piles are. I have a lot of unfinished paintings... but I just keep working on them. One day they will be done. Took me three years to write a book.
Learn to organize yourself. Make notes if you have to. I jot things down all the time. I know from experience that I will forget an idea quickly. Often the notes just sit there...sometimes for years. But sometimes I re-discover some gem and use it. You can always come back to things.
Practice makes perfect. Just keep doing it.
We learn by our mistakes... hopefully.
Self analysis is helpful.