I enjoyed this book. It's mostly quite witty, and sometimes very useful - Morton's fashion section is particularly well informed.
However, with each section, the narrative slows down - you can tell what her area of expertise is. It's a nice, lucid read, but there isn't a great deal of substance.
Morton sometimes comes across as being one of those women that conforms to the typical female stereotype (cook, clean, look pretty) - her political stance on which party to support was to choose the colour badge that would match your outfit the most. Despite some wry comments about this type of thing, you have to wonder why she'd write a book on how to be a girl if she didn't want to fall into the stereotype (and similarly, her readers).
Also, style and appearance is CONSTANTLY mentioned - you can't fix a tyre if it means that you'll mess up your hair, etc. This is quite annoying, but that is essentially the book's agenda.
Other than that, the book is very entertaining, and it certainly provides a very sketchy guide to most areas of thought. I'm giving it 4 stars, assuming that the reader had bought the book purely for the wit/amusing guides, such as "How to wear an apron with style".
Just don't buy this book for any of your feminist friends.