Your emotions are a reflection of how much your current disposition (activities/thoughts/actions) are aligned with your Inner Self. If you are generally happy/satisfied/contented then you are technically balanced.
We maintain this balance by aligning with the Truth of our Inner Being (Essential Self, Soul). This is accomplished by heightening the ability to recognize when you are balanced. We heighten this ability by meditation.
When we meditate, the objective should be to quiet our mind of excess and extraneous thoughts. As we practice meditation (a daily meditation routine) we will become more aware of, and actually experience the desired alignment of emotional balance as Clarity/Completeness/Wholeness.
The practice of daily meditation allows this balance to linger longer and longer throughout the day. Once you are aware of this balanced state of being you will notice when things/situations/people/ events… etc. are out of alignment with it. Avoid these things, and you will maintain your Spiritual Emotional balance thus be able to partake of all its benefits.