Best thing one can do for a hot spot is shave the area to allow air to get to it, and dab with witch hazel several times a day. Another strong recommendation is Bailey's Skin Rescue (Canine Coach on Call).
Both Baron and Neelah had hot spots on their heads (Baron from a tick bite and Neelah from I don't know what!) - shaved the area, cleaned well and applied witch hazel twice a day. I think Neelah healed faster than Baron because she didn't scratch at it like he did, plus she's on antibiotics for a low grade UTI.
The Bailey's Skin Rescue product is AWESOME - I can't recommend it enough!
When I bought Moose at 16 months old the poor boy had fly bites that were raw on his ears and non stop itching. I learned about feeding a quality kibble and that stopped his problem. He gets itchy feet now and then this time of year and I use Four Paws Medicated Anti-Itch Spray. It has witch hazel in it. It works great.