Blue Sage, also known as "Grandmother Sage” is a purifying herb with broad applications. It is also good for healing and cleansing rituals, its relaxing smell can be used while meditate, or burned simply for enjoyment.
White Sage is used for purification, wisdom, protection, also for the removal of spirits, negative energies, to bring peace of mind. Wherever white sage is, evil cannot be.
Smudges may help clear the air, scientists have observed that sage can clear up to 94 percent of airborne bacteria and disinfect the air. Also, when sage is burned, it releases negative ions, which is linked to putting people into a positive mood. 
Smudging requires simple ingredients like matches, smudging herbs, and a smudging bowl. Before you start, remember to open a door or window, because the unwanted energy you are trying to clear must have a pathway to get out. First, light one end of your smudge, allowing it to catch fire and burn for several seconds. Then gently blow on the lit end - the smudge will begin to glow and smoke. Lay the smudge on a heatproof bowl to catch the ashes as it burns.