“How do you treat a big toe after nail removal?”

Apparently, either the ER MD or your podiatrist did not talk to you about this! It is hard for me to believe that nothing was said to you, no paper instructions given, etc. In general, foot/toe surgery needs to elevated the majority of the first post-procedure day, and up on pillows at night. Only open-toed shoes on that foot for at least 18 days - may shower, but must pat dry the toe. No direct sun on the toe until the nail is almost completely grown in.

Leg elevation with triple antibiotic Rx with pain reliever TID.