Use your favorite mix of coffee roasted beans to brew 2 oz of espresso.
Let the espresso to stand and cold down a little bit.
Get an Old Fashioned glass and put the 2 oz espresso.
Carefully add the 2 oz of your favorite liquor (Whiskey, Ron or Brandy), this step is critical if you want a good looking cocktail. If done correctly you will get the liquor to fall to the bottom of the glass and you will see a beautiful transition between the two drinks.
Tip: Traditionally, carajillo is served warm, but you can also serve it cold, add some ice cubes if you want.
Tip: Use a liquior named "Licor 43", a spanish liquior made with a secret recipe of 43 ingredients (species, herbs, fruits), you will get a most refined taste.
Tip: Brew your coffee with some herbs (cinnamon, clove, anís, and more) to improve the taste.