1. Keep a journal.
Write down your thoughts, ideas and experiences into a journal. Your journal is a summary of the things that go through your mind and your experiences in life. Write sincerely and remember that nobody besides you will read it.
You don't have to write daily or make any sort of a set schedule for writing in the journal. You can just write whenever you feel like it and have time. Don't force yourself to write, let the habit develop naturally.
Going over your journal and analyzing it helps you make new realizations about yourself and your life.