Learning a little more about ghillie suits
As it has been previously said, camouflage is a hunting keystone and it implies not only visual camo but also that related to smells and sounds; the aim is to render the hunter invisible to the game as most as possible, especially considering that most of hunted animals have keener senses than humans.
On this regard, camo clothes are very popular and their aim is to blend the hunter with the background through shapes, colors and patterns. The basics behind such kind of camouflage is that a plain, brilliant color will be more visible respect to the natural background than irregular, background color like patterns, however the basic contour shape will be still visible, especially from the air (waterfowl hunting) and upper positions (i.e. deer hunting), thus using a ghillie suit will improve suit camo properties.
The aim of a ghillie suit is to break down the human silhouette using elements from the environment; thus a head won't be seen as a head and the arms will resemble more a tree branch than an human extremity.
To achieve such effect ghillie suits are built with loose, rough burlap flaps over an invisible nylon net where elements from local vegetation such as twigs and leaves are put by hand to break down the human shape and mimetize it with the background.
The best ghillie suits are hand made from scratch, but doing it may be time consuming; then most hunters prefer to start with a commercial ghillie suit which is later customized according to the area where the hunting takes place.
Customization includes not only adding leaves and foliage but also to cover the fabrics with soil and sand to give it a "earthy smell"; additionally odor eliminators may be used as well artificial lures.
It's important to change local leaves and twigs regularly through the day because their color changes due to wilting.
Remember that to be effective a ghillie suit must be customized according to a particular environment (see picture above), thus it won't be effective on another environment unless a new customization is made. Most of commercial ghillie suits come on green and brown tones with a bunch of neutral gray, making easy to adapt their customization to almost every woodland condition.
However, depending of the area and season you could choose an orange-brown predominant base (autumn hunting) or perhaps something greener (southern states or spring hunting).
Mastering the art of ghillie suit build up takes time and patience, thus read a lot, practice even more and assess which is what better works for you. It's a matter of assay and mistake just to find the best way to build your own ghillie suit; so get started with a commercial base and move on customizations; results will be amazing faster than you think.