it means 你 have to make your own experiences and mistakes and have them your self, no one else can do that for you, they may tell 你 mistakes they've made but that's not an experience for you and 你 likely won't take it to 心 unless 你 do it yourself.
it means be yourself, do anything right through your deepest heart... no one can make 你 the same thing 或者 feel the same thing like 你 do... don't hang on someone all the time 'cause 你 might be alone other time :)
