Yoga writings and philosophy are not really spiritual teachings but useful hints and suggestions as to how you can become a better person, they suggest how you can over come your character and behaviour faults. Yoga is designed to creating a union between your body, mind and spirit. Its objective is to assist you to modify your breath and body mindfully to connect to your greater self.
The sacred texts describes the inner workings of your mind and provide a blueprint for controlling its restlessness.

Here are the basic Yamas (behaviour towards others) and Niyamas (self observations) from The Yoga Sutra by Patanjali (circa 200 A.D.).
In the Water-Babies by the Rev Charles Kingsley Link: http://www.pagebypagebooks.com/Charles_Kingsley/The_Water_Babies/ there is a fairy called Mrs Do-As-You-Would-Be-Done-By. I loved this grizzled old fairy and in some ways to the childish me they were an introduction to the Yamas.
1.    Ahimsa:  Be kind to others.  A comprehensive do no harm: not in words, thoughts, nor actions.
2.     Satya:  Tell the truth.   Lies aren’t inherently wrong but really they make life complex and are unnecessary.
3.    Asteya:  Only take what is yours.  Remember playing in kinder garden? Share and don’t steal.
4.    Brahmacharya:  Be respectful and reverent.  Though this can sometimes be interpreted as celibacy it actually means controlling your impulses, the mark of an adult.
5.    Aparigraha:  Share. Be generous, not greedy. Let your attachment to emotions and objects fade.

To achieve at least some ability to act on the Yamas you need to apply them to yourself and the following Niyamas definitely help. In other words be nice to yourself as well as to others.
1.    Sauca:  Be pure.  Self evident really, clean body but more importantly cultivate a healthy consciousness of gratitude for what is.
2.    Santosa:  Practice acceptance or contentment by allowing yourself to seek equanimity not from outside of yourself, but from within. Breath work and meditation really help.
3.    Tapas:  Do your work mindfully. Work and let the benefits of it unfold over time.
4.    Svadhyaya:  Take time to reflect and study.  Become an expert on yourself. Learn to appreciate yourself.
5.    Isvara pranidhana:  Be humble and unassuming.  You are one of many not one above many.  Know and honour your connection to the greater cosmos.

These precepts enable you to embody yogic balance, to be the best person you can be. If you had nothing to struggle with you would probably not even be here. But here we all are for good and ill, learning, growing, loving. Our job is to give our lives meaning by exercising free will. The meaning in your life is discovered not by the practice of yoga—but by its embodiment.