Offsets are small side growths that can sometimes become new plants. Removing them is useful when a cluster is crowded, when you want backups, or when the offset already has enough size to survive on its own.
Check whether the offset has roots or a clear attachment point. Separate it gently, dry the wound, and plant it in a suitable medium without watering too heavily at first.
Not every offset needs to be removed. Sometimes leaving the plant clustered is healthier and more attractive.