You can improve you self-confidence by, walking quickly, the people that walk quickly often have more works to do and if you walk about 25% faster walking you look more important. But the better is to have a job and consequently, having some responsibilities and task, this will force us to be faster and more caution to be able to do our tasks.
Being a good speaker
Speaking well will increase your-self, by practicing you speaking ability in front of a group you can be a good public speaker. Work our Physical appearance are important bout what you feel about yourself. So that start a regular exercise In home or gym.