To build a fire, it helps to understand the basic principles of a fire. Fuel (in a nongaseous state) does not burn directly. When you apply heat to a fuel, it produces a gas. This gas, combined with oxygen in the air, burns.
Understanding the concept of the fire triangle is very important in correctly constructing and maintaining a fire. The three sides of the triangle represent air, heat and fuel. If you remove any of these, the fire will go out. The correct ratio of these components is very important for a fire to burn at its greatest capability. The only way to learn this ratio is to practice.
Site Selection and Preparation
You will have to decide what site and arrangement to use. Before building a fire consider the area, materials and tools, time available, and the purpose of the fire. Is this fire mainly for cooking, or do you plan to use it only for a source of heat?
Next, look for a dry spot to build your fire. Make sure this location is protected from the wind, and is placed near any shelter you may build. Think about where you want the heat concentrated at your campsite. Before building, make sure there is enough wood or other fuel to sustain whatever type of fire you choose.