One of the first steps you must take in your quest to developing your personality is to know yourself- discover who you are.
It is very important to know yourself in order to figure out what needs to be done to modify your existing personality.
Knowing yourself is not about knowing your favorite color, food and etc. It is about knowing your limitations and plus points. You must be aware of your abilities so that you can use them when the time comes. You must analyze yourself to be able to find out what it is that you lacking as well as ways to get better.
Are you short tempered or do you panic easily or maybe you find it difficult to speak in a group? You must identify your struggles and learn better ways to break out of your limitations.