White Sage (salvia apiana) is an evergreen shrub that grows across the U.S., mostly in high-altitude desert ecosystems. It is widely used for purification, cleansing, protection, and in ceremonies for blessing & prosperity. For this reason, many consider the White Sage plant to be sacred.
The most popular means of using this herb is to burn the dried leaves in a ritual known as "smudging". This can be done using a bundle of white sage, sometimes called a "wand", or by burning loose leaves in a fire-safe container.
Before lighting sage to start the smudging process, it is best to start with a prayer or petition to set your intention & express gratitude for the help of the plant's spirit. Then, treat your sage like incense-- light the ends of the leaves so they ignite & then quickly blow them out, allowing the leaves to smolder. Burning multiple leaves or torching a larger section of the bundle before blowing it out will burn your sage hotter & faster and create more smoke.
Once your sage is smoldering, hold it over a fire-safe bowl, plate, or shell so you don't drop ashes on yourself or in the area you're smudging. You can then waft the smoke using a feather, your hand, or by moving the sage itself up & down in a smooth motion. The smoke attaches to negative energies and neutralizes them as it dissipates.
Once you've smudged the desired items or area, set the smoldering bundle in a fireproof bowl or sea-shell and allow it to burn out naturally as you move on with the rest of your practice.