Adelizzi's rule of thumb is to always go bigger. If you're looking to camp solo, go for the two-person tent. The extra room allows for storage that you won't have otherwise. Leaving your gear outside your tent runs the risk of getting it wet or ripped off--and neither of those scenarios are optimal, to say the least.
For the solo backpacker, a Bivy sack is the most basic. It's more or less a waterproof barrier for your sleeping bag that may or may not come with pole-supported head space. It's the most bare-bones, minimalist method of sleeping and may make you feel as though you're trapped in a cocoon—but you'll be able to carry it for miles and miles.
The next step up, Quarter Dome tents are popular again, they don't provide much room for your gear. Adelizzi recommends a two-person tent or half-dome for the beginner solo tripper's maximum comfort. Many come with just one-pole setups and are now designed more vertical for more living room.
For two or three people sharing a tent, not only is it still wise to pick a larger tent but one with a garage or vestibule for gear, dogs or that extra friend, like the MSR Hubba Hubba two- or three-person tent.
When you're thinking about four or more people, like your family or close group of friends, things start to get heavy. At this point, Camping and car camping tents become the norm—and at that point you're free to set up the Taj Mahal if you'd like. Multiple rooms make these luxury shelters spacious and comfy and you can find accompanying accessories like porches, awnings, more storage space, sunshades and sheltered screens. Adelizzi recommends these types of camping tents for those who "want to get their kids into it and make regular trips to Yosemite or camp on the beach for a week with the family."
Care and Feeding is Important
You've shelled out for your first tent—so make sure it lasts as long as it possibly can. Footprints are a key lining between the ground and the floor of your tent that protects it from ripping on rocks and sticks. "I learned that the hard way," says Adelizzi, who ripped one of his own tents before her employed a footprint. "After that, you're tent is completely useless."
When you get home, wash out the dirt and hang it up to dry to avoid mildew. Store it in a cool dry place (heat seems to damage or melt it a bit) and dream up your next trip.