While most people have a good idea how to store and serve red and white table wines, sherry sometimes trips them up. In fact, poor service and storage is one of the reasons sherry is less popular than it deserves. Here are some guidelines to help you get the most out of drinking sherry.
Temperature: Finos, and Manzanillas should be served chilled, as should Amontillados and Palo Cortados, if somewhat less so. Opinion is divided on Olorosos, and I tend to let the occasion dictate; in warmer weather I prefer to chill it ever so slightly. Cream sherries are drank at all sorts of temperatures, even on the rocks with a slice of lemon. This is in keeping with their commercial character; the more ways that can be recommended to serve a drink, the more occasions a consumer might purchase it. If for some reason I have to drink a poor-quality cream sherry - for politeness' sake, let's say - I try to drink it as cold as possible to mask its flaws as much as possible.
Glasses: Because it is fortified and therefore stronger than many wines, sherry is usually served in small, tulip-shaped glasses. The traditional variety is called a copita. However, I must admit that at home I drink it from a larger Chardonnay glass so I don't have to go to the fridge so often.
Storing: Sherry has had all the aging it needs before it is released. The richer styles will last quite some time in an unopened bottle, but will not perceptibly improve from the experience. Finos and Manzanillas are much more delicate and should be drunk as soon as possible after purchase as they tend to lose their freshness just as many crisp, light, unfortified white wines do. Some experts even suggest confirming that your local supplier moves enough sherry to ensure that the bottles haven't been sitting around the store too long.
There is a common misperception that sherry, once opened, remains fresh for quite some time, like some other fortified wines (madeira, for example) and liquors. This is unfortunately not the case, and another reason that sherry is not as popular as it deserves to be with Americans is that they try it at a restaurant that has kept a bottle of Fino sitting on the bar for several months developing dust on the bottle like a reminder of the flor that once helped make the wine great. In restaurants it is definitely important to order sherry at a place that takes wine seriously and sells a fair amount of sherry. They should keep their finos and mazanillas chilled and ideally use some sort of vacuum stopper to help protect the wine once it has been opened.
At home try to finish a bottle of any of the drier sherries within a few days, and keep the wine refrigerated and stoppered after opening. Amontillados, Olorosos and Cream sherries will last much longer whether chilled or otherwise; usually a couple of months or so. This makes them a safer bet in restaurants that may not sell too much sherry generally.