Personal and shelter concealment particularly during a tactical situation is a survival skill that if you cannot master, will leave you exposed. Typically, your camouflage strategy in a wilderness environment would be “crypsis” which means you blend into your background to avoid detection.
You want to resemble your background, to confuse the human eye, and you want your shelter to blend in as well. Humans instinctively look for and try to identify a face in virtually any situation. This is likely an instinctive reaction that was used thousands of years ago to locate predators in the brush.
Animals know what a human silhouette looks like and anyone tracking you most certainly will know.
People look for faces in everything they see, and then try to identify a body to go along with it. People will look for a head, hanging arms and legs. In a tactical situation, you would look for headgear, and equipment that you would normally expect someone to be carrying such as rifle and pack. All of these features need to be broken up so what someone is seeing cannot be pieced together and identified as a human body.
Trackers will scan with their eyes and never focus for long periods at any one object, and this is particularly true when hunting for others in darkness. You would use peripheral vision to spot movement while scanning at night.
The human face is unique, so your camouflage routine must break up your facial patterns and this can be done by various methods.
Shine
You skin will reflect light or shine, in other words, and thus must be subdued with mud, “camo” sticks or paint, wood ash, boot polish or charcoal. Oily skin in particular will shine. You want to break up the face, so it is not recognizable as a face as the eyes pass over it.
Metal objects will shine whether they are painted or not in many cases. Weapons can be wrapped in strips of dark cloth for night movement, and for daylight hours, you can use strips of camouflaged clothing, which should be prepared ahead of time for this purpose and use leaves and other vegetation as well.
Scopes, to include spotter scopes, and binoculars, eyeglasses, boot/shoe eyelets, watch faces and knives all can all give away your position because of light reflection. Use a black magic marker and/or camo paint to subdue smaller metal objects temporarily and you can also use mud, cloth, and vegetation for larger parts or objects. The glare from eyeglass lenses can be lessened by blowing fine dust onto the lenses.
Fit In
Obviously, geography plays a role, so blending into your background means you would use what is available in your environment. Ideally, you will know ahead of time whether you will be in a region that is snow covered, sandy, heavily forested and so on, so you can prepare accordingly. If you are setting up a static position, such as a guard post or even sniper position, you could use a Ghillie suit. They are time consuming to make however, and can make movement more difficult, so carefully consider the time and effort needed to make one properly. The suits would be heavy to carry or wear and not ideal to pack if you are continually moving for long periods.
Heavy vegetation makes ideal camouflage, but can also conceal the enemy as well, so diligence is required. A branch with the leaves attached along with bunches of grass secured to parts of your body and equipment will help break up any recognizable outlines. However, broken branches and ripped up vegetation is evidence of your presence to anyone tracking you, so be mindful of leaving a trail that can be followed.
A human walking upright is immediately recognizable so you have to do something about this when moving in the open if you suspect others are tracking you. When crossing roadways or paths crouch or even low crawl across. Trackers can spot movement out of the corners of their eyes so move slowly and deliberately especially in open areas. Pause often if you suspect or know you are being tracked so if you are spotted while in heavy vegetation your movement cannot be as easily tracked. Pausing will also allow you to listen for others moving.
Trackers will attempt to guess your destination and will try to set up an ambush point where they expect you will end up. Backtrack and move left to right to get to your destination to confuse anyone attempting to anticipate where you may come out of the brush for example.
Overhead Surveillance
In years past those on the ground could hear aircraft flying about and could seek cover or conceal themselves until the aircraft moved on. Today however with drones readily available to almost anyone, you may not be able to hear or visually detect any air reconnaissance. Overhead cover is important and you should always assume there is overhead surveillance.
The typical drone operating during daylight hours will have a camera (s) that may very well be transmitting video and pictures back to the operator in real time. This means the information received is time sensitive and in some cases, this would be actionable intelligence, which could be used by anyone tracking you.
Use overhead cover when moving about and stay in the shadows when resting, and know where you are casting a shadow because it can be spotted from overhead or from a higher elevation. You may be standing behind or under a tree but your shadow is not. Experienced trackers look for these types of signs.
Drones may also use thermal heat seeking devices at night that can detect body heat. You can use water by immersing yourself in it if the weather is warm to mask your heat signature or use a thermal blanket to keep your heat signature from displaying.
You probably cannot totally mask your heat signature from thermal cameras, but you may reduce it enough to make it look like a small mammal and not a human. Snow caves in the winter can also deflect your heat, but be very careful about chilling yourself to the point of hypothermia in cold weather.
Do not climb over objects you can crawl over, or walk around, and of course never silhouette your body against the skyline on a hilltop. Lie down before you would crest the top and inch your way up over the top so you can view the surrounding area.
Base Camp
Staying in one place means you can be tracked to that one place. However, if you used the proper camouflage and evasion techniques to reach your base camp your worry is now keeping a low profile to avoid detection by anyone that happens to be in the area or enters the area.
Once at base camp you cannot put up a Day-Glo orange tent and that is the end of it. A tent is not ideal in any tactical situation because you can be essentially trapped in one if the camp is overrun, and your vision is limited while inside. Of course, if you have enough personnel that can act as guards then tents may work, but if by yourself in a hostile area, it is not recommended you set up a tent.
Some will set up tents however, and then set about hacking up all the vegetation in the immediate area to camouflage the tent. This of course is a sure way of being noticed. If you do cut up vegetation and use as camouflage it will wilt after a few days and will immediately standout. Additionally, signs of cut brush can be spotted from long distances and from the air.
You want to maintain a small footprint, to avoid detection. Use tarps or natural shelters in the area, so as not to disturb the area. Use live vegetation as camouflage by stringing your tarp between trees, over limbs and so on without cutting or trampling all of the brush and grasses in the area.
Use a Dakota fire hole to conceal your fire and if you do build an open fire never place it in front of your shelter. Sitting around staring into the campfire is not something you want to do while in hostile territory. Prepare so you can survive nights without a fire. This of course typically only applies if you are being tracked, or are in a combat situation and must avoid detection.
Waste must be buried to include human waste immediately and do so, so it is not obvious you were digging in the area. Pick up a large rock carefully, and then dig your waste hole where the rock lay and then carefully replace the rock.
Drones are a concern while at camp and if you were able to plan, you could use camouflage netting to conceal your shelter from overhead surveillance. Otherwise, use natural features in the area for concealment, such as the overhead canopy.
Do not use the same path for every visit to the latrine or any water source to avoid creating a worn path that can be spotted from the air or ground. Use weapons for hunting other than firearms.