Most Helpful Guy
I think you just eventually learn to not care what others think aha0
Most Helpful Girl
First, you got to feel comfortable of who you are. Make a list of 50 reasons of why you are amazing. Examples would be I am amazing because I volunteer at animal shelters, I lend a hand in my family whenever needed, etc.
Second, go change up your look. Get a hair cut. So, if you have long hair, perhaps dye your hair or even cut it short.
Lastly, everyday infront of a mirror, you have to recite the 50 reasons and tell yourself you are beautiful. When saying it outloud, you have to actually BELIEVE what you are saying. Don't just passively say it. BELIEVE IT.
I know it will feel odd at first, but trust me, you will see your self confidence rise in no time.
Do it for two weeks, and you will see the change in no time. Do it for a month, and you will have a new you. :) Tell me how it goes.1