I usually put a Tablespoon or so in my 18-20 oz bottle that I fill with Brita filtered tap water several times during the day, usually Apple Cider Vinegar but occasionally White Wine vinegar that I get in bulk from my store. I've been doing it so long that I prefer the tart flavor more than the sweet stuff that is marketed.
I do warn people it is an acid and it is an acquired taste. If you swallow wrong it WILL lock up your breathing and put you in dire straights for a few minutes (How long can you hold your breath while your eyes are bulging out?). I do that once in awhile and it is not pleasant.
If you are interested, start out with a large glass of water and a small teaspoon of AC vinegar and take it in small sips. Anything further is up to you.
It's supposed to help one's body metabolism (weight loss), but I haven't witnessed it, but I also don't take it at the levels they suggest. Most of the benefits and uses of vinegar have all be scientifically evaluated and proven to be true, but for health benefits its like taking a multi-vitamin, it may help the body but it is not a cure all.
There's no sodium in vinegar, just acetic acid with fermented flavoring. In fact, distilled white vinegar is almost pure acetic acid and doesn't really fall in to the category of a true "vinegar".
Vinegar makes a good weed killer so be careful using it around your plants. There are thousands of uses and books written on the subject.
The Vinegar Institute - Recipes