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