Iodine was effective for me. I used LugolsIodine in a small pump stray bottle. Wash your feet and then spray Iodine between the toes. It took less than a week to get rid of it and it has not returned in well over a year.
Lugols is very staining, whe reas potassium Iodide or sodium Iodide are clear so will not stain. I have not verified whether these work as well because I did not have them when I had athletes foot. I do now have potassium Iodide but have not needed it for athletes foot because it has not returned.
Also be careful that the fungal spores do not get back on your feet from socks/shoes etc.
Washing clothes with some Borax might be helpful to destroy any fungi.