Maximum cleanliness, silver sulfadiazine cream (SSD, sold under names like silvadene), and monitoring for infection (signs of pus, injury getting worse instead of better, inflammation, increased/different discoloration sometimes) are usually best for burns outside of the vet visit. And of course, fixing the issue that created the burn.
Just as a note since I do have a bioactive setup - doing bioactive well is expensive and somewhat tricky. Just be aware of that since it sounds like your funds are pretty limited.
