Key 3: Respect Yourself
It might sound obvious, but a great majority of the people I meet do not have even a basic level of self-respect for themselves.
Here's a quick self-test to see if you love yourself: Do you speak poorly about others? Do you avoid doing some things because you aren't good enough? Do you think yourself better than others?
If you answer yes to any of those questions, then you'll need to work on loving yourself more. It's the key to good relations with others, for getting along, for having luck in life, and living a fulfilling life.