Wash your citrus, scrubbing gently if non-organic.
Peel with a vegetable peeler, avoiding the white pith as much as possible. Place the peels in a non-reactive bowl.
Gently mix in an equal amount of sugar, by weight, to the peels. A kitchen scale is best for determining this, but you can also eyeball it using the proportion of 1 cup of peels to ¼ c of sugar.
Stir to coat the rinds with sugar. Let the mixture sit for 24 hours at room temperature, stirring every so often and pressing on the peels with a wooden spoon.
After a day on your counter, strain the syrup through a sieve, pressing on the solids to extract as much syrup as possible. Store in a jar in the refrigerator.