Dressing your brand newborn baby for the first time is slightly daunting, since most of your focus has probably been on your pregnancy so far. Its good to get a few basics ready for the hospital trip home. During the last trimester of your pregnancy you can browse the web for online stores , look especially for layers, these are best as the hospital tends to be very warm. 

Some Tips 
A good rule of thumb is that your baby needs one more layer of clothing than you do. 
A snowsuit provides a great buffer against the cold and snow. Once your baby is dressed in his outfit for the day, you can simply slip him into the snowsuit just before you go out or get out of the car. Snowsuits have form-fitting legs and arms, and most are equipped with hoods. Look for one with a good layer of insulation, such as fleece or flannel, and a water-repellent exterior fabric. 

Most body heat escapes through the head, so always put a hat on your baby before going outside in winter. If his hands are exposed, put some gloves on them. If he tends to suck on his hands, keep an extra pair or two handy. Make sure your baby wears socks to keep his feet toasty, too. 
On freezing days, you can wrap a blanket around his snowsuit. 
Once you're indoors, even if it's just for a quick stop at the supermarket, take at least one layer off your baby so he won't start feeling clammy. Otherwise, the dampness will make him colder when you get back out in the winter air. And if you've covered your baby with a blanket in the car, you should take it off once the car warms up. 

Safety is paramount : In order to work properly in a crash, car seat straps must be snug. Make sure your baby isn't wearing clothing that's too bulky for his car seat, and don't put blankets between your baby and the straps. Instead, dress him in clothes that allow the straps to go between his legs, adjust the straps to allow for the thickness of his clothes, and pile blankets or other bulky layers on top of the harness straps instead of under them. 
 

As long as the weather isn't too unfriendly, it is vital for your baby to get fresh air every day, whether it is in a buggy, sling or backpack. A furry seat liner for your baby’s buggy will provide extra bottom warmth , and coupled with a blanket on top  to create a cosy cocoon. 

Make sure to keep in mind while you are working up a sweat pushing or carrying him around, your baby is just sitting there , he'll get chilly well before you do. How to you know when your baby’s had enough though? Just be aware of his behaviour. If he is happy to be out at first , maybe he starts fussing after a bit, he may be trying to tell you that he's chilly. It's a good idea to check his fingers, toes, ears, & face regularly, and go inside before he gets fretty. 

Stay warm: If your baby gets very cold, make sure not to try to warm his skin by rubbing it.. Instead, hold his skin against yours. 

Make sure clothing is snug and fitted well, straps cannot be slack and must be fitted close to baby in case of sudden breaking or crashes. If he's wearing a bulky coat or think blanket , this will compromise the effectiveness of the car seat straps. Think layers are essentail, where shoulder are clearly visible and not lost in the bulk or plile of the fabric. And of course make sure that straps can easily fit between his legs