There are many factors. Mostly I would say it has to do with first acquiring the necessary self-confidence and then practicing a lot (which is also a big part o

There are many factors. Mostly I would say it has to do with first acquiring the necessary self-confidence and then practicing a lot (which is also a big part of acquiring a lot of confidence). A very good book, with lots of exercises (that you should practice often if you really want to get better) is The Charisma Myth (http://www.amazon.com/Charisma-Myth-Science-Personal-Magnetism/dp/1591845947/ref=sr_1_1?ie=UTF8&qid=1431318586&sr=8-1&keywords=charisma+myth http://www.amazon.com/Charisma-Myth-Science-Personal-Magneti...). Good luck in your learning journey!