How to be more feminine?

my friends told me I'm not that feminine and ladylike. They say I'm always acting super childish and seem to be very mischievous and naughty.

Actually everybody had told me that at least once.

Even my ex told me i dont look trustworthy because i look and act childish even though i really am trustworthy. :((

I dont even act that much childish I just don't take everything so seriously.

I really want to seem more mature.

I don't know what to do. How should I behave. :((

How to be more feminine?
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