If you are trying to save her and are unable to take her to the vet, this is what I would do. My bumblefoot surgery healed well on my hen, but she got a secondary infection when the pinfeathers on her foot (faverolles with feathered feet, oi) became infected after abrasion from the vet wrap. We also had a period of mushy, wet weather and I think it contributed to the infection developing at the abrasion site. I had put her outside after the bumblefoot surgery as I didn't want her to get alienated from the flock, and though I kept her in clean bandages, the ground was mucky (we got >4" of rain in one evening!) and it was impossible to keep her dry outside.
So, I brought her in and soaked her feet in quite warm, salty water, and cleaned them as well as I could.
I lanced the infected area, and used a sharp, sterile scalpel to scrape away as much as the infection and infected flesh as possible. It's important to note that the infection was not gooey or pussy, but rubbery in texture. If you can not use a scalpel, use a sharp blade that you are comfortable handling! Though it sounds contradictory, this is easier with a blade with a rounded tip, and not a pointed one. Keep it clean.
While doing this, I encountered a lot of blood around one toe. I immediately packed with powdered cayenne (yes, the kind you cook with). and applied pressure until all bleeding stopped, which took about 10 minutes. Cayenne has minor natural antibacterial properties and will help blood form a clot and scab. It will NOT cause a burning sensation! Cayenne is one of the most painless things you can apply for surface clotting. I have used it on myself before. Just keep it out of your eyes, and your hen's, of course. It will burn, there.
After the infection was opened to the air, and as much scraped away as possible, I packed the site with bacitracin (neosporin) and closed with vet wrap. I kept her indoors to keep her feet DRY and CLEAN... the two big important ones! Every day I removed the bandages, to inspect the infection site and to apply clean bandages if necessary. I re-packed the wound with bacitracin once per day.
After the wound was not weeping or wet looking, we removed the bandages to let the wound breathe and harden, still keeping her inside where we could control the surface, and kept her feet DRY and CLEAN.
She healed to a solid scar within a week, which made it safe to let her outside again, and now (about 3 weeks later) you cannot even tell that her feet had any problems at all.
I hated having to re-integrate her into the flock, but it was better than losing her! A few days of bulling was worth saving her feet (or worse).
I don't know if this will help you but I hope you can glean some information from it!