Depending on the severity, angle, and type of wound it may or may not be better off wrapped. Some wounds are better left open and cleaned frequently, and some are better wrapped, some need tubes put into them to train, some need to heal inside out, some need to heal outside in, some need antibiotics....my point being, if it is severe at all, I would really call the vet out.
If she absolutely cannot have the vet out, I think Abby has the best cleaning advice, though I really don't know anything about bacon grease, and I would stick with betadine and a triple antobiotic cream. I would at least call a vet and describe the symtoms, and ask for treatment advice.
I am not meaning to sound rude, but I have heard on several occations that so and so does not have the money to have the vet out for various things (pregnancy check, emergencies, etc.). I just don't understand this. As horse owners, we really need to be prepared for these kinds of situations. Sometimes people get hit with astronomical bills that they had no way to prepare for, but I think it is important to always keep a bit of a cushion in an emergency horse care fund.
For your friends case, depending on the wound care needed, your area, the need for emergency call or not, medicines needed, follow ups, etc,...care could cost around $500 (maybe a bit less). (I am basing that on what my emergency vet call cost for when my boy got a laceration on his pasturn on a trail ride, which required sedation, a nerve block, stitches, and antibiotics).
To save money, I try to give my own vaccines, minor wound care, buy wormer and other supplies in bulk deals, etc. But there are some things that you just need the vet for.