From a few bottles to hundreds, proper storage of your wine is very important. To cellar doesn't mean that you necessarily have a great room filled with hundreds of wine bottles. It simply means you have decided to care for your wines long term and you need a place to put them.
First you should understand that cellaring wine is not always right for every bottle of wine. Some wines are meant to be drunk young. Others are better with age. If you're unsure, try buying several bottles of your favorite young wine and drinking one each year until you hit upon the perfect balance between all the complexities your wines have to offer.
Having decided that you're cellaring wine, not just storing a few bottles in the pantry or next to the stove on a windowsill, then you need to allocate a suitable spot for your wines to be at their best and brightest when you're ready to dig them back out.
Choose a cool, dark place, where your bottles will remain undisturbed. The most important factor in deciding on a location should be consistent temperature. Remember, you're looking for the least amount of temperature fluctuation for your wine. Do you have a side of the house that gets less sun? Choose it. Then be sure that the spot you have chosen is in the dark. Like a vampire, light is wine's arch enemy. Most modern wine bottles have built-in UV protection but if you've begun to make an investment in your wine collection, but do not yet have a "cellar", you should cover the windows or any other source of constant light.
The objective is to leave your wine in a temperature of around 50-55 degrees and approximately 70% humidity. This is ideal. But don't be discouraged if you can't achieve these exact levels in your designated wine cellar spot. You should pay more attention to fluctuations in temperatures than to achieving spot-on temperature and humidity recommendations. And try to think ahead. You may begin cellaring with only a few bottles, but will almost definitely want to keep adding, adding, and adding to your collection. Plan for more than you think you'll need and you won't be sorry.
Be a patient wine drinker. Your wines are lying on their sides, in a dark cool place because you want to protect them and be assured that they're aging as best as possible. You can visit them, but it's unwise to keep picking them up and looking at them. Let them rest in peace until you're ready to pop the cork!