The goal of Stoicism is for you to experience Happiness, eudaimonia. To achieve this you need to live with wisdom, courage, justice, and moderation. In Stoic words: you need to live virtuously.
Unless you're a sage, this is easier said than done.
How to live according to the Stoic virtues? How to get to a more balanced state? Through discipline.
Stoicism is a system to provide us with this discipline and live smarter. One of the most important Stoic insights is that our thinking not only influences our actions but that it also defines our emotions. Not being aware of this causes suffering.