Fill a 12 ounce glass about ¾ of the way full with ice cubes.
Pour in the vodka.
Pour in the lemonade.
Stir to combine.
Garnish with lemon slices and serve.
Notes
As you can see, this drink is equal parts vodka and lemonade. You can make this drink as small or large as you would like to fit the size of glass you are using.