Summary from TED's video. Writing flows and grammar.

hello guys ! please help me to correct this paragraph to improve my writing.
I tried to make a summary from TED's video.
An important skill that should be owned by people is self-confident. How to build our self-confident totally in our lives? Firstly, repetition is a way to train the self-confident showing an ability to accomplish tasks. When they do practice regularly with the same task, it will incorporate their belief for completing their responsibilities. Secondly, a huge persistence will affect people's mind to brave performing an equal activities with having self-affirmation. For instance, Muhammad Ali, a well-known person of fighting-sport, could fully believe himself that he was the greatest person in this planet. He built a positive behaviour without cogitating what the others said about him. As a result, the notion of self-assured is an immense ability for helping humans in order to achieve the better future-live.

Everyone should learn to gain self-confident. Since it is believed that self-confidence brings more happiness, self-confident people are naturally more successful. Here are some techniques to build self-confidence .

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