Cellulitis in darker-skinned individuals appears as a red, swollen, and painful area of skin, often affecting the legs, arms, or face, with the redness sometimes appearing darker due to pigmentation differences. It is caused by a bacterial infection, commonly Streptococcus or Staphylococcus aureus, which can spread rapidly and lead to fever and chills. Treatment typically involves oral or intravenous antibiotics like cephalexin or dicloxacillin, along with rest and elevation of the affected area to reduce swelling.