In a glass or plastic container, suitable for the size of jewelry to patina, squeeze a quarter size drop into the bottom of the container.
Add water.
And stir.
It should be a strong yellow color.
Drop your metal in and pull when it is black.
Rinse in the baking soda/water solution to stop the patina process and neutralize the chemical.
More info when using liver of sulfur.
Warm or hot water will cause a quicker and darker coloration on the metal.
You can get this by boiling water in a kettle or using hot tap water.
A coffee mug warmer works great to keep Liver of Sulfur warm if you going to be using it several times.