Most time we do so many things that we felt is worth doing but we never know that it is not worth the time ,
1.things like your desire to have everything you do not have.There are some people who will never have what you have now(that which you do not appreciate you have) and vice versa, so why wasting your time.
2.Comparing yourself to everyone else steal your happiness, instead of comparing yourself to everyone, why don't you start thanking God for who you are.
3.Another one is thinking about who you used to be rather focus cause you are growing and growing comes with experience
4.Worrying about the mistakes you have made,I am guilty of this, I do worry a lot about mistakes, don't forget that Mistakes are part of learning, rather than worrying about your mistakes why dont you make it a motivation and not an excuse
5.Wasting your life on self deception, your life cannot improve by decieving yourself, it is your best to be honest with yourself
6.Do not make everyone's definition of success and Happiness yours, because your own definition will always be different from theirs
7. Don't try to impress anyone, you do not need anyone to like you because everyone cannot like you no matter how you please them
http://itsseanney..com/2016/02/7-things-you-need-not-to-waste-your.html