A Personal Plan is the process of documenting life goals and creating the action plans to achieve them. These goals are typically centered around career; business; lifestyle; finances and self improvement.
This is a summary of your ideas into a concise and unambiguous mission statement. Just like you would have a mission statement for your business, you should have a personal statement that drives you.
Essentially, you are asking yourself really important and tough questions on your intentions; inspiration and your commitment to achieving these goals.