Before storing a wine, get some information on how it should be consumed. Some wines don’t gain anything from being kept in bottle, since they are already ready to be drunk when they are placed on the market. Some examples are wines produced in the Vinhos Verdes region and red wines from Alentejo and Ribatejo.
If you wish to build a cellar, it is important you choose the wines according to your personal taste. The number of existing bottles should be proportional to your consuming habits.

The cellar should be an open space, protected from light and temperature fluctuations (which should be between 7ºC and 13ºC). When there are major temperature fluctuations, the wine may escape through the bottle’s cork or capsule, meaning the wine heated or the cork overdried.

Air humidity is another aspect to consider: it should be between 60% and 75%. If the place where the wine is going to be stored is too humid, you may buy lime blocks to absorb humidity or a dehumidifier. If, on the other hand, you need to increase air humidity, it is best to water the floor (if possible). To make sure of the temperature and humidity levels, you should get a thermometer and a hygrometer. A more expensive option is to get a refrigerator cellar, where temperature and humidity are constant and easily controlled.

The cellar should have good air circulation to quickly remove unwanted smells (such as, for instance, the musty smell).

Once in the cellar, the wine should be moved the least possible, so the ideal is to plan how you are going to arrange the bottles before you start storing them. Usually, the bottles are kept horizontally so that the wine stays in contact with the cork. This way, the cork won’t dry and let air in. The best bottles should be nearer the ground, since it is the most humid area in the cellar. Tawny Port, Madeira and other fortified wine bottles should be stored vertically, since they are made up of elements that may damage the corks when in permanent contact.