0. Start by thoroughly washing the lemons, removing any residue so that it doesn't contaminate the flavor of the limoncello. It's important that the lemons are untreated.

1. Using a vegetable peeler, remove the lemon zest, being careful to leave the white pith. Excessive zest can make the limoncello more bitter. Also, be careful not to get lemon juice on the lemon zest.

2. Place the chopped lemon peels and the alcohol in a tightly sealed glass container. Close the container and cover it with aluminum foil to keep out light. Store in a closed cupboard and let it steep for about 2 days.

3. In a bowl, combine the sugar and water. Stir until all the sugar has dissolved. Then, strain the lemon peels and add the alcohol. You'll notice that the alcohol has already acquired the typical limoncello color and aroma. Stir until completely incorporated. Pour your limoncello into one or more glass bottles and you're done!