I am reading this book, "Shadows of a Witch", by Shewolf Silver Shadows, and part of this excellent grimoire of all things wiccan and witchcraft deals with the darker aspects of witchcraft and shadow work. The "grey" area of enlightenment where we acknowledge both the light and the dark, the positive and negative within all things, including witches.
Often times <too many times imo>, modern day wicca is perceived as light or fluffy or all smiles and no frown and so on, you are aware of what i'm talking about, lol. For some this is true and if that is the path you wish to trod, then Do What Thou Will by all means. For some, we recognize the balance between forces, we are not perfect and we learn and teach on a daily basis from lessons learned in shadow work and the very bowels of shaman-ism itself.
There are many ways to begin shadow work, each way unique and personal, as all shadow work is. I strongly suggest a firm knowledge on the subject before beginning and an idea of which technique you will use.