Step 1: In a medium saucepan over medium heat, mix sugar and water until the sugar dissolves. Add blueberries and lime zest, bringing the mixture to a boil. Let it simmer until the blueberries burst, about 5 minutes.

Step 2: Remove from heat and let it cool for 10 minutes, then strain the mixture into a clean jar. Allow it to cool completely.

Step 3: Combine sugar and salt on a small plate. Rim each glass with a lemon wedge, then dip it in the sugar-salt mixture.

Step 4: Divide tequila, triple sec, and lemonade among 4 glasses. Fill each glass with ice and top it off with blueberry syrup.

Step 5: Garnish with a lemon wedge and serve.