All the tools to balance your 3rd or Solar Plexus Chakra will help to increase your inner power and strength and therefore, your self confidence. 

As I am reading Serge Kahili King's new book, "Creating Reality," I see how many of the same tools are used in the Hawaiian shamanic tradition.  King describes shamanic tools using four levels or world views for increasing self esteem...

On the physical level, or in the objective world view, King recommends skill development - increasing your energy, strength of body and mind, and consciously changing your posture. On the second or subjective level, he recommends self talk - self praise and increasing your aura; on the third level or symbolic level - creative visualization, guided imagery, dreamwork; and on the fourth level, or holistic level where we are all one,  modeling the behavior of someone/something you’d like to emulate. Check out Huna wisdom at www.Huna.org.