Just as a single unforeseen change in weather can turn a mild day into a problem for clothing, a cold start followed by a mild midday can turn clothing into a problem for planning. And while it is uncomfortable to start off with too little insulation, it can make you miserable later on as you suffer from the wet, rising heat you had forgotten about while sitting.

Start with the first hour, not the forecast average

This temperature is very important for the early part of a hunt. The first part of time is spent standing still, walking slowly or sitting down for long periods. Therefore, a forecast for mid-day that looks quite warm needs to be read in the context of the coldest time of day for your hunt. This does not mean that you cannot wear less warm clothing for the latter part of the day, just that you will need to be able to reduce layers without storing them in your bag.

Plan your starting temperature on the basis of the activity you expect to undertake in the first part of your hunt and with reference to the degree of wind exposure, plus the space your pack is going to occupy in your clothing. You don't need the same amount of insulation for a long, steep climb as you would for a quiet sit.

Give base layers one clear job

Base layers should only be doing one job: to remove moisture from your skin. If the base layer is too warm for the uphill sections then the sweat in it will become a problem later. It's better to have it be too light for the uphills than too heavy.

Make sure the clothing in between your base layers doesn't restrict your movement. You want to be able to detect moisture in places like the back, chest, armpits and lower back where your pack sits. If your base layers are making you warm and damp then that moisture is going to start to cool as soon as you stop moving.

Don't mistake a base layer for an emergency layer for cold. If it becomes soaked with sweat, adding another layer on top could hide the problem but not fix it. Slowing down your pace of travel, venting and changing to a dry layer can be more effective than adding another layer.

Build insulation that can leave your body

This layer needs to provide warmth, but should also be able to be easily removed and stowed when temperatures rise during pauses over longer periods. Consider how well the layer will insulate when wet, and pack light. A thin layer that can be compressed into a pocket is much better than a thick bulky one that will dominate your pack for the return journey.

Test each outfit by laying out all layers and putting them on. Add a pack and simulate activities like sitting, kneeling and reaching forward. Check for irritation from sleeves at wrists and from collars at the neck. Also, check for restriction at the shoulders and by straps. Uncomfortable clothing will get in the way of otherwise mundane tasks and lead to frustration when you need to move fast for field decisions.

Make sure that you can reach the layer you plan to remove for warmth and have it higher in your pack than any wet clothing. Do not bury your warm gloves or socks under food and other gear in your pack.

Treat wind and precipitation as separate problems

Just because there is warm air does not mean you do not need a protective outer layer. Wind can make quite normal temperatures feel very cold indeed, and it is also possible for relatively mild weather to turn unpleasantly wet. Your outer layer must be able to protect you from the sorts of weather that you anticipate encountering, without becoming too cumbersome to wear comfortably when you are moving.

Pay attention to the hood, cuffs, and front opening of your outer layer. These areas can dictate how you are able to vent excess heat or allow wind to penetrate into your layering system. Open up or loosen outer layers as you move, before you start to feel the onset of heat stress and the fabric becomes wetter than you'd like.

Do not underestimate a waterproof and breathable outer layer shell. This is not just something to wear on your outward journey. A wet outer layer, a leaking seam or a broken zipper can become a serious problem during a long wait or on your return journey, especially if you are exposed to the weather. Make sure to check your outer layer for any weaknesses before you leave and repair them if necessary.

Use symptoms to decide when to adjust

Some of the indicators for over-burdening your body with clothing include: persistent shivering; numbing of fingers and toes; trouble fastening zippers, buttons or laces; feeling of extreme tiredness; an over-urge to hurry along; damp base layers; a cold strip running round the waist; soaking of socks; and, wet clothing, especially down the back of the legs and along the soles of feet where sweat can run and then rapidly cool.

Heat has signs too – see above for symptoms of cold – get rid of an unnecessary layer before your next stop. Confusion, feeling of increasing weariness, aching or shivering when cold or sweaty and flushed when hot – all of these are reasons for stopping your excursion and getting appropriate help.

In every change in activity, check for the following symptoms: skin, hands, feet, wind on skin and last layer to be removed. These checks will only take a few seconds and enable you to avoid very serious problems with your clothing.

Pack for the return, not just the departure

Remember that your return journey could be traveled while cold, tired and with your outer clothing to be wet. Pack one dry alternative to the worst offending layer and additional hand/foot layers if space permits. Keep wet clothing separated from your dry outdoor gear rather than squashing it into the bottom of your pack.

Inspect your outdoor clothing before you pack it for your trip. Check for flattening of insulation, worn or breaking stitches, blocked up vents, worn elastic, breaking zippers, and dampness or even moisture trapped in pockets and folds. Dry your gear fully after use, and follow the care information for the outer fabric and the insulation used in your clothing. Note that dirt and human body oils can affect the comfort of your gear and its performance, and be very careful with washing your outdoor clothing. Aggressive washing and wrong heat can sometimes even ruin your clothing.

The best clothing system is one that can be summarized in a few words: 'moisture managing base layers, adjustable insulating mid layers and wind / rain protection outer layers with a change of clothes for weak points'. Such a system is better than others because it promotes good decisions with changing circumstances rather than allowing discomfort to prompt a hasty and possibly ill judged decision to press on and become (very) lost and spend a lot of time and effort with the problem when it could have been sorted out quickly and easily hours before.