At the most basic, add a lemon or cucumber slice to a glass of cold water or a few in a pitcher filled with ice and water. To make them sweeter, make a simple syrup (equal parts sugar and water, cooked to dissolve, start with 3/4 cup each).... here are some ideas:
Pineapple Ginger Fresca - make the simple syrup but add a few sliced freshly cut ginger. Let cool, then strain the mixture to remove the ginger. Puree pineapple to water 2 to 1 ratio of fruit to water. Then add to a pitcher of water. Stir in sugar syrup to sweeten.
Cucumber Lemon - make the simple syrup and let a few lemon slices soak in it while the syrup is cooling. Remove the lemon when cool. Puree 2 cucumbers (skin on) with 3 cups water to blend. Strain to remove seeds and skin and pour in a pitcher. Add enough water to fill up the pitcher add juice from 1 lemon. Add simple syrup to taste.
Strawberry Thyme - make simple syrup and add thyme while cooling. Strain to remove thyme. In a blender, blend strawberries with 2 - 3 cups of water. Strain out the solids and add to a pitcher. Add additional water and syrup.
Basic Fresca Recipe -
2-3 cups fruit, fresh or frozen, chopped coarsely (melons, berries, citrus)
6-8 cups water
-Use agave syrup instead of simple syrup
-For a little kick, add chili pepper
-Canned crushed pineapple will work in lieu of a blender