What most of us do not understand is that the best we could be is what God has made us. Shocked? When God was about sending us into this world, He first determined what we would do and then, what we would do dictated how we would look like. It is an ignorance of purpose that makes us desire to be someone else instead of what/who we are.
That you are physically challenged, slim or fat, tall or short, ‘shapeless and not beautiful’ as you may say, are not reasons for living below your potentials. Until you discover what you are meant to do, you will never appreciate why you are like that. Every time you complain about yourself, you are only displaying your ignorance of purpose and telling God He is not perfect in His work.
When you know what you are meant to do on earth, you will better appreciate how you look like because if you had not been who you are, you probably would not have been able to carry out what you were ordained to do. So, tell yourself you are custom-made for your assignment and the best you can be is who you are now.
Let your assignment motivate you and consume you to the level you care less about what people and more about what you are doing, and sooner than you expect, those who laughed at you will soon come to appreciate you for who you are.