Seriously. All high achievers scribble and write stuff down, whether a list of daily tasks or just simple reminders. Notes taken can range from something as simple as “pick up milk & eggs on the way home” to stuff like “call the bank manager after lunch”.
There are multiple ways to do this, and as many things in life, the best way is a combination of solutions.
You can have and create notes on your mobile phone, add reminders for events or time constrained actions, write up things in your calendar and best still you can delegate a lot of these tasks to a personal assistant whom can have access to a cloud based solution for adding, tracking and managing ideas, reminders and task.
But by far the most you will gain from going old school. Have a small portable notebook and pencil on you and just scribble down thoughts, ideas and maybe even an impromptu to do list.
Other than being very readily available it has the golden characteristic of being private. Some thoughts and goals you might not want to make your personal assistant privy too. Some ideas are purely private and as such should stay so.
And once you get into the habit of notching down your goals and thoughts, you will begin to understand the value fully.