Proper first aid for a dog bite puncture wound focuses on thorough cleaning and infection prevention, since these wounds can trap bacteria deep under the skin. Immediately wash the area with soap and running water for at least 5–10 minutes, then gently allow it to bleed slightly to help flush out germs. After cleaning, apply an antiseptic (like povidone-iodine or chlorhexidine) and cover it with a clean, sterile bandage. Keep the wound clean and dry, and change the dressing daily while watching for signs of infection such as increasing redness, swelling, warmth, pus, or fever.