What do I do with this biopsy hole while I wait for a month to see surgeon to remove more cancer? (photo)

Round scars shrink, when left alone, but your end result will depends on your Mohs' surgery, so all you need to do now is keep it clean.Soap and water will do, unless it shows sign of infection, but it is unlikely to become infected if treated appropriately: i.e. soap and water, clean towel or hair drier and a dry dressing.Remember a dry dressing is a barrier between you and the outside world, a wet dressing does not act as a barrier and has to be changed.Good luck with the Mohs'

Open biopsy wounds are not likely to become infected if left open, in fact it is better for them.  However they should be protected from the sun.  If for cosmetic reason you would like to cover your biopsy site you can use hydrocolloid moisture-retentive wound dressing, such as DuoDERM which can be purchased over the counter at most drug stores.   To ease your mind Basal cell carcinomas are often very slow to grow. Waiting four or five weeks is not uncommon for some patients to just get an appointment for consultation in some busy practices. 

If you have to wait that long I would consider washing the wound with antibacterial soap, pat dry, swab with alcohol, then place either a duoderm thin spot over area or a bandaid advance healing waterproof bandaid. They can stay on for up to 3 days before changing in some instances. You may want to try getting into someone sooner if you have biopsy report in hand you maybe able to do this. I know a guy dr Jeffery Whitworth in Clifton area that is a great guy and skilled MOHs surgeon you could call upon and see if he can help in your care.