be yourself (but you must also have manners)
accept yourself. (e.g. if you feel you’re gay for the moment, then accept it)
accept on what you have (e.g. if you’re not that good in singing, don’t make a big deal about it)
laugh at your simple mistakes (everybody’s not perfect)
shrug off all negative perceptions from others, haters don’t really know you.
focus on the positive aspects of yourself.
focus on the positive aspects of others.
be interested on other people. (but not to the point of stalking them, give them privacy.)

The best way to boost your self confidence is show off your good side, and gain compliments, for you would get them because you are deserving. and firstly, take a chill, because not always people are looking at you or judging you/your actions, so just relax. mistakes are okay sometimes, no one notices, because everyone makes them! so don’t worry!

also, try getting a new look for yourself, like a make over, for required or not, that usually ups one’s mood as looking fresh and good catches a lot of others’ attention, in a good way!

but most important, at the end of the day, just be yourself! people will accept who you are, so no need to be self conscious!

Never ever try to compare yourself with another each one has his own personality so just be yourself and be at peace with the world.