Instructions
Make the simple syrup. Combine the sugar and 1 cup of the water in a small saucepan and bring to a gentle simmer over low heat to dissolve sugar. Once the sugar is completely dissolved, remove from heat to cool.
Squeeze the lemons. Roll each lemon over your cutting board, pressing down as you do. This will help them to release their juice. Cut in half and squeeze. Repeat until you have one cup. You might not need all the lemons, but try to save at least one half if you want to garnish your glasses.
Combine. Add the cooled syrup to your pitcher, followed by the lemon juice and remaining 4 cups of water. Stir, taste, and adjust; add a few tablespoons of sugar if it needs to be sweeter or the juice of 1/2 lemon if it needs more tartness.
Add ice. Add ice to pitcher if you think you will drink the whole pitcher right away. Otherwise add ice to each glass.
Garnish. It's optional, but garnishes are fun. Try a slice of fruit, a sprig of mint or other herb, or a flower (such as lavender or nasturtium). If you've infused the simple syrup with an herb (see below), it's helpful to garnish the glass with the herb used.