@casportpony pretty much described what the vet would do. They would also show you how to properly wrap the foot which you would have to keep dry and change every few days while continuing an antibiotic and pain meds.
It really depends on how bad it is as well, because what looks like just a simple bumble foot case, could be a serious underlying joint infection... I just lost one of my ducks to a joint infection. I could never figure out why she was stumbling around like she was drunk yet seemed completely normal other than having a "bit" of bumble foot. She was at her normal weight, eating/drinking just fine, no break/sprain, no swelling, no fever, and her legs were still responsive. I took her in and started her on some Vitamin B Complex, Nutri Drench, an electrolyte/probiotic, and an antibiotic as well, but when I finally decided to check out the "bit" of bumble foot a week later, it was already too late. It had been
beyond too late for a very long time.
After she died, I did an autopsy to see just how bad the infection was, and I ended up cutting all the way down the foot and up the ankle, and I discovered that the infection grew and twisted around all the bones and joints which looked like stringy roots that wouldn't even detach if I pulled really hard... If I had taken her to the vet right when I noticed the "drunken behavior," they probably would have put her down. I'm amazed that she didn't even have a fever like most of my birds usually do with an infection.
This was also the same duck that had a dislocated toe joint surgically removed two years prior on the
opposite foot...