Welcome to the Forum
If you have the time, check thru the past threads in the Armor and Techniques sections of the forum. About six months ago, someone posted the same question and there were a bunch of answers using everything from gauze to tinfoil.
Having said that, I use either gauze or bridal veil material - the gauze I wet and let shrink and then paint it a dark color (OD or Brown). Once dry, spread it and tack it to a piece of board. Then shoot on a thin coat of contact cement (Elmer's works well). Then while still wet, sprinkle it with crushed paprika leaves. When dry, fold it, roll it or stretch it over your model. you can do the same thing with the bridal veil, you just don't need to wash it.
BTW, for you who have never had the pleasure of working with the damned things, a camo net is an invention of the Devil. They come in sets with hexes and diamonds (the shapes) which have to be assembled (guess who gets to do that) and it takes 3 sets to properly camo a Hummvee. When assembled, they are heavy and bulky. They will catch on any protrusion on the piece of equipment you are trying to cover and you will be amazed at the number of things on your body they will find to catch on. (buttons a real pain when putting one up - and the military has yet to discover velcro or zippers for most of the clothing it issues). It's positively amazing how quickly the order of "Get the nets up" will empty the area of available bodies.