| Making layered shots is one of the chief reasons I love to tend bar. Also known as pousse-cafes, these drinks are fun to make, usually tasty, and delightful to look at. One usually serves these in a clear glass cordial glass, also known a shot glass. This is because each layer of the drink is selected not only for its flavor, but also for the way the colors appear next to each other. Each layer has a different density, so they tend not to mix with each other.
There are several different kinds of layered shots, but the technique is much the same for all of them. It requires a steady hand and a sense of balance, as well as a touch of artistry. A table of liquor specific weights is helpful as well.
First decide what liquors you are going to use. A favored selection for the group I play bartender for is the "Chocolate Covered Cherry", though you could change the liquors for an American Flag or any other drink you'd want. To make a triple-C, you'll need Irish Cream, Grenadine, and either Khalua or Creme de Cacao.
Since the grenadine is the heaviest of the fluids, you'll pour it first. Pour it so roughly a third of the shot glass is filled.
Next comes the Creme de Cacao/Kahlua. Pour the liquor gently down the side of the shot glass, filling roughly another third. If you make a mistake and pour too quickly, let the shot glass stand for about a minute. The two fluids will rapidly separate themselves. Another method is to invert a spoon over the top of the glass, and pour that way. The idea is to prevent mixing of the liqueurs.
Finally comes the Irish Cream. Be very careful with this step, as Irish Cream and Kahlua or Creme de Cacao do not separate as readily as the previous two liquids.
Now serve, and enjoy!
Check out the table of liquor specific weights. | 
