Never undervalue anyone, including yourself. Never forget to appreciate everyone that comes into your life, they bring joy, love and life lessons. Failing to appreciate everything you have accomplished, no matter how small, is basically telling yourself you don't matter, you're reinforcing the "not good enough" you were told as a child. When you fail to value yourself, you fail to value others too, therefore losing out on what that relationship can bring to you. So for today start by deciding how can you appreciate those closest to you?