Shopping for a sofa? Here's what you need to know

A lot of your life happens on your sofa. It's the place you perch as you catch up with friends over a glass of wine, where you nestle in to read that bestseller you've been dying to get your hands on, and where you fall asleep waiting for your teen to get home safely from that first date.

It's no wonder that picking the sofa that's right for you can be so fun — and so difficult. I've seen folks agonize over this decision more than any other interior design choice. Here's a guide to picking a sofa you'll love for years to come.

• Loose cushion: The cushions are separate from the back of the sofa (but you can also have a semi-attached cushion). These create a more casual look. A plus is the cushions can be removed and cleaned. If you want a less formal sofa that's soft and comfy, this might be the right back for you.

• Tight: The back is all upholstery, with no cushions. I'm partial to this style because it creates a cleaner, more formal look and leaves you lots of room to toss in accent pillows.

• Pillow: The back is made up of several large, unattached pillows instead of a cushion. If you have young children, beware: The pillows may end up being used to make a fort on rainy days.

• Channel: In this variation of the tight back sofa, the back is made up of several panels.

• Curved: Instead of the back and arms of the sofa being distinct pieces, in this style the back curves around to form a solid line with the arms.

• Rolled: One of my favorites, rolled arms are common on more traditional sofas. The arm curves out and is lower, making it ideal for napping.

• Square: This style is tailored and boxy, more contemporary.

• Tight: On a sofa, this is a firmer, tailored seat that does not have loose cushions. Usually you find tight seats on settees or formal sofas.

• Bench: One of my favorites, a single cushion or bench seat has a clean, crisp appearance. Single cushion sofas can get squished looking in the center if you opt for all-down cushions, giving you sloppy appearance. I recommend down-wrapped foam or spring-down cushions.

• Cushion: This popular pick features two or three loose cushions that are not attached to the base. T-shaped cushions are those that wrap around the arm of the sofa.

• Skirted: If you love a traditional look, you might want a sofa with a skirt. Be warned, though: Skirts show dirt. Shoe polish wears off on them, as do the body oils of pets who sleep against the sofa.

Fit your body. Your sofa needs to fit your body, not the other way around. If you are a petite woman, your sofa should be smaller in scale. If you are a big lumberjack of a man, you'll need a larger piece. If your sofa needs to fit lots of body types, add pillows and an ottoman to make those with short legs more comfortable.

The right dimensions. Create harmony in your space by picking a sofa that is in proportion to the other furnishings in your room. In the past, people typically looked for a new sofa because they were tired of the fabric on their old one. Today, it's often people wanting to replace a too-large sofa they purchased, whose scale is out of whack with their room.

The right tone. Your sofa needs to match the level of formality of the room. For a more formal room, for example, select a tight back sofa. For a casual space, try loose-back cushions.