Stuff all the radishes in the jar of your choice. A bowl will work too if that's all you have.
In a measuring cup, combine apple cider vinegar, salt, sugar, and warm water. Stir to dissolve the sugar and salt. Pour this pickling mixture over your sliced radishes and let them set for an hour. After an hour, cover and store in the fridge for up to three weeks.
Nutrition information is not exact, since you don't drink the pickling liquid. At least I don't.