I had to ask my daughter....

Some only drink the juice and other's eat the pickles and yet others do both. Those who drink the juice do so out of paper cups, mostly, but any cup will do.

It also has to be a certain brand... I think it's Claussens? Sp?

Going by memory, which is not at all trustworthy these days... I think they tried bananas at first and bananas had limited success. With the pickles/pickle juice not a single leg cramp since.