Make the blueberry syrup: Mix blueberries, sugar, and water in a small pot. Then, bring to a boil and simmer for 10 minutes. After that, strain and cool.
Fill a cocktail shaker with ice cubes.
Add vodka, lemon juice, and blueberry syrup to the shaker.
Shake for 15-20 seconds until well chilled.
Fill a Collins glass with fresh ice.
Strain the mixture into the glass.
Top with lemonade and stir gently.
Garnish with fresh blueberries and mint.