Use a vegetable peeler to remove the peels from the lemons. Try to remove only the outer yellow skin and as little of the white pith as possible. Transfer the lemon peel to the mason jar.
Pour the wodka over the peel in mason jar, screw on lid and place in a dark cool place for 2 - 4 weeks.
Prepare a sugar syrup of the water and sugar — bring the water to a simmer and stir in the sugar to dissolve; allow to cool. (add more sugar or water, until you reach a flavor you like)
Add the syrup to the wodka and lemon peel mixture. Let it infuse for another week or two.
After it has been infused long enough, line a strainer with a large coffee filter or a fine sifter and set it over another clean mason jar. Strain the infused vodka through the filter.
Fill nice bottles with limoncello. Serve ice cold, straight from the freezer.
Note: if you are using alcohol with a low percentage of alcohol in it, do not leave the bottle it in freezer overnight, as it will freeze solid. Just put it in the freezer for two hours before you want to serve it.