You can say this over your Book of Shadows:
In the realm of magick this book shall reside
No one but the chosen shall see what's inside
If breath be to air as passion to fire,
Let harm come to none, this is my desire
If life be to earth as water to emotions
This book be filled with magickal potions
May the Gods protect it, keep it from harm,
And upon it bestow power, magick, and charm
No one without wisdom shall peer at its pages
Or the knowledge inside handed down through the ages
This book be it mine, it harbors no fears,
The knowledge obtained through blood, sweat, and tears
My magick's my passion, the spirit's my guide
This book may she bless it with spirital light
And let only her children read of its rite
For those of the Wicca truly can see
this is my will, so mote it be
SOURCE: The Wiccan Garden, as taken from The Complete Idiot's Guide to Wicca and Witchcraft by Denise Zimmerman and Katherine A. Gleason