If using liquid sweeteners such as agave or maple syrup, or if your honey is already runny, simply combine the lemon juice, water, and 1/3 cup of sweetener in a large pitcher. Stir well to dissolve the sweetener, then taste and adjust by adding more, if desired.
If your honey has crystallized or is thick in consistency, gently warm about 1 cup of water in a small saucepan over low heat. Add 1/3 cup of honey, stirring continuously until it fully dissolves. This should take no more than a minute. Remove from heat and pour the honey mixture into a pitcher. Add the remaining water and freshly squeezed lemon juice, stirring thoroughly to blend the flavors. Taste the lemonade and adjust the sweetness by adding more honey, if needed.
Refrigerate until chilled, then serve over ice for a crisp and refreshing drink.