Awaken is the most important thing to power up a character. Once the character reaches its max level, it can be awakened to increase the star level and stats. Additionally, some of the characters acquire secret techniques, which are special moves requiring more chakra than Ninjutsu, as being awakened.
What are needed to awaken?
Awakening materials
Awakening requires specific awakening materials by characters. For example, Naruto Uzumaki ( The Worst Loser ) at star level 3 needs Awakening scrolls ( Heart Book ) to be awakened.
Ryo
It also costs Ryo, which was a currency of Japan in the past. A player can earn Ryo by succeeding missions and as reward for deceiving conditions during missions.
Do abilities (enhancing using character of same name + title) remain after awakening?
Eg. Enhancing a 5* Gaara (protector of the Sands) using the same character to acquire ability BEFORE awakening him to 6*. Will the ability reset or am I safe to enhance?