Dreams about hair often symbolize your identity, self-expression, and how you perceive yourself in relation to others. In your dream, having big hair that is dyed blue could represent a desire for individuality or a need to break free from societal or familial expectations. The blue color might signify creativity or a unique perspective, suggesting that you want to express your true self.

Your attempt to hide your hair with a witch's hat and a hood indicates a struggle between your self-expression and the pressure to conform to your parents’ preferences. This could reflect feelings of insecurity or fear of judgment regarding your choices.

Overall, this dream suggests a conflict between wanting to embrace your identity and feeling the need to conform to the expectations of those close to you. It might be helpful to reflect on how you can balance your desire for self-expression with your relationships. Consider having an open conversation with your parents about your choices and how they make you feel, which could lead to a better understanding on both sides.