Boil a kettle of water. Consult the instructions on the packet of the unflavored gelatin regarding the volume of water to be added to each packet of gelatin. Typically, one cup per small gelatin package is about the right ratio.
Measure the boiling water and pour it into the bowl. Add the gelatin powder from the package and stir the gelatin into the water. It will dissolve quickly.
Add a cup of cold water to the bowl and stir the mixture. Refrigerate the gelatin solution for two to three hours until it is set.
Create a thicker gelatin mix by reducing the amount of boiling and cold water used in the mixture, or alternatively by adding additional packages of unflavored gelatin powder.