Story points are a spendable currency that player characters can use to unlock talents in their tales, upgrade and enhance their attributes, and more.
Story points can be spent at two times: (1) as the final step in creating a character, and (2) at any time during play outside of an encounter. To spend story points, simply announce to the narrator what upgrades are being purchased, and at what costs. Then, mark that those upgrades have been purchased, and reduce the story points on the character sheet. A character cannot purchase upgrades that it cannot afford; story points do not expire, and cannot be lost in any way, so saving them for the right time is perfectly reasonable. Characters will earn more story points at the end of each encounter - expect to get a handful each time (the starting story points represent approximately 2-3 encounters worth).