Layer bourbon and citrus-sage syrup in a highball glass with ice; stir.
Top with apple cider and garnish with an orange slice and a few sage leaves.
Notes
On Proportions: The above recipe allows the bourbon to play a major part in the composition. If you prefer a less strong liquor flavor in your drinks (like my husband), feel free to add more apple cider or syrup to taste; although I suggest using the syrup sparingly as too much more could make the drink cloyingly sweet (unless that's your goal!).