Combine ginger, thyme, and apple cider vinegar in a small pot with a lid. Heat the mixture to a simmer, then cover, reduce heat, and let simmer for 30 minutes.
Remove from heat and add in the garlic. Let it cool a bit before stirring in the honey. You want it just warm enough to help dissolve the honey.
Pour the mixture into a jar and cover it with a lid. Place it in the fridge for 24 hours.
Strain into a new clean jar or large glass measuring cup to remove herb solids and return the liquid to the original jar. Label the jar with the name of the herbal preparation and the date.
As soon as you feel an illness coming on, take 1-3 tablespoons per day. If tolerated well, you can take additional doses. Feel free to dilute it in water. Warm water is particularly soothing.