Match your use: for dipping, choose the sauce with the thickest texture (duck sauce, apricot preserves mix); for glazing, choose a sauce you can simmer to cling.
Start with the listed ratio, then adjust after tasting: add vinegar a teaspoon at a time for more tang or simmer 1-3 minutes for thicker body.
If the substitute is fruit-preserve based, stir until fully uniform and simmer briefly so the vinegar and preserves emulsify.
If the substitute is ketchup/BBQ/hoisin based, simmer to mellow sharp notes and improve shine before tossing with food.
Use immediately or cool and store covered in the fridge up to 1 week.