
Style
There are two basic options for a newborn: infant carriers and convertible car seats.
Infant carriers are generally good for about the first year and function as an entire travel system: They latch into a base that stays in your car and can also be snapped into specific strollers or stroller frames. (If you decide to go this route, make sure your carrier is compatible with your stroller.) This means when you’re out with baby, there’s no need to unbuckle and buckle (and -- gasp -- risk waking up a sleeping baby) when you take him from home to the car to the stroller and back again. For suburban families who use both the car and stroller frequently, this is generally the way to go. Look for a handle that’s comfortable for carrying --this becomes more and more important the older (and bigger) baby gets. If you live in a city and will be taking cabs or for some other reason will be using lots of different cars, make sure to get a carrier that can also be installed without the base.
Convertible seats simply stay in the car. You’ll have to snap baby in and out every time and there’s no carrying option or separate base, but the advantage is they can be used much later into babyhood. If you’re looking to save money and will generally be using the same car, this is a good option.
Position

Installation
Once you think you have your car seat installed correctly, get it checked out by an expert. Your local fire department or police station should have someone trained in car seat safety who can make sure everything’s really in place. (Save time by calling ahead to make sure the car seat expert is at the station before you drive all the way there. Also ask if their certification is up-to-date. Child Passenger Safety Technicians need to be recertified every two years.) The most common mistake parents make is simply not installing the seat tightly enough. See if yours is properly in place by holding the car seat at the belt path and trying to move it from side-to-side and front to back. If you can move the seat more than an inch in any direction, it isn’t tight enough. If you have a 3-in-1 or convertible car seat, make sure the seat belt or LATCH belt is correctly in place. Triple-check the seat’s owner’s manual to be certain. If the entire installation process proves too overwhelming to tackle on your own (it happens to even the best of parents), your local expert can walk you through the entire process.
Harness
All babies need five-point harnesses. Look for one that’s easy to adjust -- when you take baby out of the harness, it’s best to loosen the straps and open the harness entirely, rather than simply unbuckle and try to wriggle baby out. While it might seem intimidating to readjust the harness every time you put baby in, you’ll quickly become accustomed to it, and will find taking baby in and out much easier. Also, when you set up a rear-facing car seat, make sure the shoulder harnesses are at or below baby’s shoulder level. (The opposite holds true for front-facing car seats, so it can be easy to misadjust.)
Energy-absorbing foam
During an accident, this is what keeps baby safe and protected from impact.
Head support
A newborn’s heads need careful cradling, since he’s not yet able to hold it up on his own. Look for a car seat that comes with a special insert to support your infant’s head. (Only use inserts manufactured by the same company as your car seat -- otherwise, you risk an improper fit.) If this still isn’t enough support, you can roll up receiving blankets around your baby’s head to keep it in place. Skip neck pillows -- while they may seem supportive, they can actually be dangerous in an accident.
Side protection
Since side-impact accidents hold the most potential danger, it’s essential that your car seat provide adequate protection. This means deep side walls and adequate barriers around the head, so that baby’s head, neck, and spine will stay aligned even during an accident. The government currently only has standards for front-impact collisions, so you’ll need to do a little detective work on this one. Look for research and evidence on the manufacturer’s website that support any claims about side-impact protection.
Comfort
Does the material and padding feel soft and snuggly -- like something you might not mind sitting in? This might sound like a luxury, but trust us -- anything that helps soothe baby will feel more than essential in the next few months.
Registration
Make sure to register your car seat when you buy it. This way, you’ll be notified of any recalls, updates, new manuals, or any other important info.
Expiration date
Yes, car seats have expiration dates. Normal lifespan is about six years -- after that, the plastic can become brittle. This is especially important to look at if you’re borrowing a car seat from a friend or relative. (On that note, only accept hand-me-downs from someone you truly trust -- make sure you know what the car seat has been through before you put your own baby in it. For that reason, you should never buy a car seat at a secondhand store.)
Baby’s position
Once your car seat is selected and installed, it’s time for phase two -- getting baby into it. One common mistake is not making the straps tight enough. Check by doing the pinch test: If you can take your fingers and pinch the webbing of the harness together, it’s not tight enough. If you’re feeling unsure, pay your fire department or police station another visit and have them check baby’s positioning. Setting your ego aside is definitely worth the peace of mind you’ll receive.
Blankets
These are essential during cold weather. Since bulky jackets can affect the way baby sits in the car seat and impact the way it performs, it’s better to dress baby normally, then keep him warm by covering him in cozy blankets.