For starters, it's easiest for me to monitor Myra in cold weather if I wear her on my front. I can see and feel her face and hands. I know if she's taken off her hat. I can tell by the look on her face if she's still enjoying herself or if she's ready to go inside. I feel like I can better block her from the wind when she's on my front, too. As far as her attire, I dress her in light layers. See those polka dots on her legs? Those are leg warmers over her pants. Typically, her pants ride up exposing her skin, this way she's completely covered. You'll notice she isn't wearing a coat , boots, or mittens because her torso, arms, and legs will be covered by my coat (another reason I like wearing her on the front!). The hat is important because her head will be exposed. And she has no hair. But mostly the exposed head part in general. I make sure to check her frequently because I don't want her to get too warm and start to sweat when it's so cold outside or that could be bad, too.
Although I do wrap Myra, we've been using a soft structured carrier (SSC) a lot lately because she thinks I'm a jungle gym while trying to wrap her, so a SSC is just easier. Many wearers particularly enjoy using their wraps in cooler weather (again, is a high of -6 still considered "cooler weather"?) because there is much less open space for drafts. Wraps are often known for a more snuggly feel, but use whatever you're comfortable using!
This is the coat I wore when I was pregnant with her. It is big enough to cover a pregnant belly or, so far, wearing a baby. There are coats made specifically for babywearing, too. Her feet don't dangle out, but there is an opening at the bottom of my jacket. I just hold my hands there to keep us both warmer. When getting ready to head outside, don't forget about dressing yourself-hat, mittens, scarf, whatever you might want to keep yourself warm, too. Of course, be extra cautious with your own footwear and be aware of the conditions on the ground. It's easy to slip and fall in Minnesota winters!
If you'd rather wear baby outside your own coat, make sure he/she is fully bundled and monitor frequently. Happy Babywearing!