Winter layers for a day of going in and out
On a cold city day, the part that often catches you is the change of pace: waiting at a stop, then walking quickly, then sitting inside. Make the outside layer easy to remove and give your indoor outfit enough shape to work by itself.
Give each layer a job
Try a comfortable base, a warm knit and an insulated jacket with space to close over both. Add full-length trousers, warm socks and shoes suited to the surface. Cover the join between sock and trouser when you sit. Start with the likely coldest outdoor wait; if you expect long exposure or strong wind, reconsider your outer layer and coverage before choosing colors.
Keep a route for heat to escape
Wear the jacket with a knit that can also stand on its own at lunch. Fasten the jacket outdoors and open it before a warm indoor queue. If a thick base layer makes you too warm indoors, use a removable midlayer next time. A scarf that packs down is easier to manage than a second bulky jacket.
Check the whole outfit at once
Zip up, sit down and cross your arms. If the jacket drags at the shoulder or pushes the knit into your neck, thin or change one layer. Check boot traction for the actual surface; a heavy-looking boot in a photograph tells you little about its grip.