Juice the lemons until you have 1 cup of fresh lemon juice.
In a pitcher, combine the lemon juice and sugar.
Stir until the sugar is fully dissolved.
Add 4 cups of cold water to the pitcher.
Mix well to combine all ingredients.
Taste and adjust sweetness with more sugar if desired.
Chill the lemonade in the refrigerator for at least 30 minutes.
Serve over ice cubes in tall glasses.
Garnish with lemon slices if desired.
Enjoy your refreshing homemade lemonade!