The amount of manpower you have is limited by injuries, strength, and the general health of you and all other survivors. Even injured persons who can not walk can use their hands to fabricate materials for the shelters so plan to include everyone in the effort.
Any man made materials you have access to can be used as well: Floor mats from a car, seat cushions, plastic grocery sacks filled with leaves. . . Anything that will distance you from the ground and keep you dry. The ground steals heat rapidly and water pools in low spots so this step is critical.
These two branches will form a 45 degree triangle to hold the spine up off of the ground. The mouth of the shelter will form a 45 degree triangle with the longest side being the ground the two poles are set on and the point of the triangle above it. The point of the triangle is where the spine branch will rest because the two branches cross and form a small “X” to set the spine on.
The idea is to block all light from being seen while in the shelter. Pinpoints of light mean air (and heat) can easily escape from the inside. Covering the shelter with as much insulating material as possible is limited by the strength of your spine pole and of course the amount of available materials. Even in an open field you can gather bunches of field grasses and make a ‘pile’ shelter, so covering your ‘A’ frame should not prove too difficult. Weigh down any materials you cover the frame with to keep them from blowing away in the wind. Mud, branches, and even snow will hold the materials down. Also, snow is a natural insulator.
Feel free to ‘stuff’ the interior of the shelter with dry grasses, leaves, or other materials (rugs, blankets, pillows). The extra padding will help keep you warm as well.