As a way to clear the mind and create seeds for future thoughts, write all interesting ideas down as they occur. Writing creates a space for 'the answer to go'.
Avoid waiting for 'the right moment' and build ideas as the fragments come to you. Start capturing immediately and use the passing of time as leverage to let things accumulate naturally—it is the necessary precursor to 'the right moment'. Ideas increment automatically when they are captured
Try to note all possibilities, including the bad ones. Put all the ideas on the table. Filtering slows down the process of brainstorming and clogs the creativity faucet. Rank and organize it later. Optimize for enumerating as many options as possible.
Write just enough to be understood later. When you can trust that it will re-appear when you need it, it's easier to have a 'mind like water' and relax.
Can be part of Productivity trinity.