To activate rose quartz, start by cleansing it to remove any negative energy. You can do this by rinsing it under running water, placing it in sunlight or moonlight for a few hours, or using sage smoke. Once cleansed, hold the crystal in your hands, and set a clear intention for its purpose. Visualize your intention surrounding the stone, infusing it with your energy. Then place the rose quartz in a prominent location to keep its energy active.