In a small pot whisk soy sauce, water, cornstarch and honey together until smooth. Add any of the optional additional ingredients you are using (vinegar, garlic, ginger, etc) .
Bring to a boil. Reduce heat to medium and whisk constantly until desired thickness is reached, about 8-10 minutes. Do not leave unattended it thickens quickly once it gets boiling and will rapidly burn. It will continue to thicken as it cools so remove it before it looks to the consistency you are after.
Taste and adjust as desired. If too thick, thin with additional water to desired consistency.
Sauce will thicken as it stands. If too thick simply whisk in a few tablespoons of warm water at a time until desired consistency is reached.