Self-love happens when you start loving yourself. Just the way you love your mom or dad, you love yourself. Are you the person who looks into the mirror to find out if he/she has a curved nose or big eyes? Or are you are the person who knows how to appreciate God's creation? If you say yes to the second question, it is undoubtedly a sign of self-love.
By saying that you should learn to appreciate yourself, doesn't mean that you should never try to improve yourself. But, there are certain things which are good deep inside your heart waiting for your positive approval. Suppose, if you are a kind hearted person who loves to get someone out of a tight spot, feel proud of it. There is nothing wrong in doing that. This you do because you love that character of yours.