I recently bought Leil Lowndes' book "How to Talk to Anyone: 92 Little Tricks For Big Success In Relationships". I found the tips within easily applicable and very well recieved: essentially what it said on the tin! On the other hand, buying this book - "How to Feel Confident" - I felt it was targeted at those who struggle to say "hello", as opposed to those who can say "hello" but struggle with being confident and the rest of a relationship. Genuinely only one piece of advice did I find helpful (to do with raising energy levels by being expressive, crazy, and physical when you wake up). Indeed, ironically, I felt myself becoming less confident as going through the book: it keeps on reminding the reader that they are a "Shy"; I felt branded into a category which I do not believe I necessarily am.
Therefore, in conclusion, I would advocate for anyone who simply wants to improve their communication skills (which, by implication, would increase confidence)to get Leil Lowndes' book "How to Talk to Anyone: 92 Little Tricks For Big Success In Relationships". As I found this book - "How to Feel Confident" - would only be helpful for the enlightenment of the socially removed.