The short answer is this:

Spiritual direction is a conversation in which three people take and active part: the director, the directee and the Holy Spirit. In this conversation, the one receiving direction (the directee) is seeking the help of the director in order to grow in his relationship with God, and to figure out what God wants him to do and where he is leading him in the concrete situations of life.

There are some times in life when the decisions we have to make are momentous, such as deciding our vocation. Other times they are smaller, but the important part is that we are trying to make sure that our decisions are really in accordance with what God wants and his way of doing things, and not based on our own mistaken preferences or on something as fickle as our emotions.

God bless,