The layer against your skin decides whether the rest of your kit works. Get it wrong and the best jacket on the hill will not save you.
Merino or synthetic
Merino — Woolpower, Harkila's Base Active range, Deerhunter's Quinn undershirt — holds warmth when damp and resists odour, which matters on a stalking trip where you are wearing the same layer for several days. Synthetics such as Jack Pyke's Quick Wick and Sitka's CORE lightweight move sweat faster and dry faster, which suits hard walking in mild weather. Most stalkers end up owning both and choosing by the forecast.
Long johns and the sitting problem
Walking generates its own heat. Sitting does not. If your day involves a high seat or a long wait on a ride, add long johns rather than another layer on top — Harkila's Base Active and Woolpower's 200 with a fly are both cut for that job.
Fit
Next-to-skin means next to skin. A base layer worn loose traps air in the wrong place and stops wicking altogether. Buy it snug and let the midlayer do the insulating.
Then layer up: outers and midlayers, fleeces, socks and waterproof clothing.
