In a saucepan, combine equal parts of granulated sugar and water. For example, use 1 cup of sugar and 1 cup of water to make 2 cups of simple syrup.

Heat the mixture over medium heat, stirring occasionally until the sugar dissolves completely.

Bring the mixture to a boil and then reduce the heat to low and simmer for about 5 minutes. This will help to thicken the syrup slightly.

Remove the saucepan from the heat and let the syrup cool completely.

Once cooled, transfer the syrup to a clean bottle or jar with a tight-fitting lid and store it in the refrigerator. Simple syrup can be stored in the refrigerator for up to 1 month.