Ingredients: transparent glass, salt, liquid soap, grapefruit juice, and alcohol (e.g. disinfectant, rum, vodka, etc.).
The initial step comprises of spitting on the glass and adding a touch of salt to it. At that point, include some fluid cleanser (like the one you use for washing the dishes), juice from a grapefruit, and a few drops of liquor. When you have everything on the glass, mix the blend, et presto.
The saliva contains cells from your mouth that have DNA inside them. The detergent is used to break down the membranes that protect the DNA, and releases it into the recipient. The salt makes the DNA denature* and precipitate, while the grapefruit juice neutralizes the proteins that could damage the DNA.