Put salt, sugar, and cinnamon on a small plate.
Lightly brush rim of glass with syrup or water and place glass upside down on plate. Rotate glass to coat rim in mixture.
Add apple cider, tequila, and pumpkin spice syrup to a shaker filled with ice. Shake well to combine.
Add ice into prepared glass and strain mixture from shaker into glass.
Garnish cocktail with a rosemary sprig and additional ground cinnamon, if desired.