How can I get rid of my stuffed up nose by tomorrow afternoon?

Quick fix. Although, my philosophy in the practice of my specialty, has always been what is the diagnosis before treating the patient. There are a number of treatment possibilities. Otc Neo-Synephrine nasal spray for a maximum of 3 times a day for 3 days. Sudafed, a decongestant, for 3 days. Rarely a high but short course of oral steroids or nasal steroids. If all of these fail, see an ENT doctor.