1 Huffing. 2  To huff an inhalant, a rag is soaked in an inhalant and pressed to the mouth. 3  Sniffing or snorting. 4  In this form of abuse, fumes are sniffed or snorted directly from an aerosol container. 5  Bagging. 6  To bag an inhalant, fumes are sprayed or poured into a plastic or paper bag and inhaled. 7  Spraying.