This recipe graciously stolen from the Food Renegade.

The Goods
juice of 12 lemons
1/2 cup honey, preferably light colored
1 cup of whey (the liquid drained off of yogurt)

The Gettin’
1.  Put all ingredients into a gallon sized container.  Top off with water (distilled might be best; we actually like the taste of ours better with tap water.)  Mix thoroughly and cover tightly with a lid.
2.  Keep at room temperature for 48 hours.
3.  Depending on how humid your climate is, some amount of yeast and/or mold could form.  Don’t worry about it – just filter the finished product through some coffee filters.
4.  Make sure to refrigerate after filtering, and enjoy!