Build the combination around the day
Imagine a day that includes a cool morning, a train ride, a city walk and a warm indoor stop. Each stage may call for different clothing. Start by identifying the layer next to your skin, the piece providing additional warmth and the protection intended for wind or rain. Their roles can overlap, but should remain clear enough to help you decide what to remove or add.
Try the complete combination on. A lightweight jumper is of little use if its sleeves bunch uncomfortably inside the jacket. Move your arms, sit down and wear the planned backpack. Notice seams lying on top of each other and collars that clash with a scarf or jacket fastening. Good fit in each separate garment does not establish that they work together.
Choose pieces that serve several of the situations you expect. This does not mean packing a different outfit for every stop. A jumper comfortable during both the journey and an evening meal may replace an additional item. Still consider particular requirements for a planned event, rather than discovering at the door that your entire selection is unsuitable.
A forecast checked close to departure is more useful than a general idea of the season. Wind, rain and changes between morning and afternoon affect the selection. Plan an adjustable combination without packing a complete outfit for every imaginable weather condition. Extra pieces add weight and do not necessarily make daily choices easier.
Plan for layers when they are not being worn
Check where the jumper will go after you take it off. It should fit in the daypack without displacing the water bottle or blocking access to important items. Clothing knotted around the outside can slip or become wet. Giving it a planned place in your bag makes the transition between outdoors and indoors easier.
Read the materials' care instructions. Some garments are difficult to wash during a trip or take a long time to dry. On a longer journey, the combination should also work around a planned laundry day. You do not necessarily need two of everything; pieces that work in different combinations may be more useful than exact duplicates.
After a trip, note which layers were worn frequently and which stayed in the suitcase. That is a better basis for the next packing list than a fixed rule about the number of jumpers to bring. A workable selection fits your pace, the places you visit and your own temperature preferences. It does not have to look the same for every traveller.
