Simple Configuration: To save costs, the trap can be stretched at the top and bottom corners between three external poles. A sapling is attached to the back pole to lift the cone and provide support for a collector. For this configuration, the trap needs ties at each top and bottom corner. Cloth ties or a light gauge (e.g. 20) of flexible galvanized wire are suitable. If traps are to be left unattended for a long period of time, use 18 gauge wire. Vinyl or nylon ties like those used with tents are best in terms of wear and tear. Wires attached to the netting at the back of the trap may result in tears. If wire is used, reinforce the back corners with cloth when the trap is sewn.
 

Robust Configuration: This is my current preference after operating traps in areas with persistent high winds and occasional severe thunderstorms.  This system uses three light-weight poles (5-10 mm in diametre) inserted into sleeves sewn into each corner.  These internal poles distribute tension evenly, avoiding tears. They also make the trap much easier to work with.

Suitable bamboo or plastic poles are sold for garden stakes in 4 foot lengths.

The poles can be inserted into sleeves made by rolling back and sewing up the edges of the blue wings, and by sewing an extra sleeve into the netting at the back corner of the trap.

 

A Third Option: If traps are well-sewn and symmetrical, sturdy support poles can also be inserted directly into corner sleeves. The poles will then need to be pegged with guy ropes to maintain tension; this can be difficult in soft ground.

I prefer  external supports with adjustable wire ties at permanent sites. Simpler systems are suitable for short-term use. In remote locations, the trap can be set up at the front with pegs, guy ropes and two light-weight poles. A sturdy external pole for the back, and a flexible suspension pole, can be cut on site from saplings.

Choose a level site in an open area away from buildings, shrubs, trees, etc., and with little or no afternoon shade. Exact positioning can be important in a home setting where there are many physical features to distract flies from investigating the trap.

Mow grass over a 2-m radius and keep it trimmed. The trap should be set close to the ground, just enough to leave a convenient gap for some hand trimming. The effect of setting the trap higher, as is often done for catching certain tabanids, has yet to be investigated in any detail (see Practical Notes).

At northern latitudes the trap should face WEST or SOUTHWEST, even if using an odour bait, as biting fly activity will most likely be focused on the sunny side of the trap during the afternoon (orientation). In the tropics, it is likely more important to set the trap facing downwind, so that flies encounter the entrance first when following an odour bait plume.
 

Pound a 6-foot iron T-bar well into the ground to serve as an anchor at the back of the trap. Any sturdy pole will do. A T-bar provides a convenient groove to hold a flexible suspension pole.

Insert thin bamboo/garden poles into the corner trap sleeves. Shove the inner pole at the back of the trap lightly into the ground, leaving about a 15-cm gap to the T-bar.  Use a wire tie with a loop to attach the top of the pole to the T-bar, so that the front corners can be located and positioned.
 

Find the two front corners by stretching the trap between the three inner poles; shove the two front inner poles into the ground, stretching out the bottom of the trap. Pound two external poles into the ground at the front corners (e.g. light metal, 5-foot T-bar gardening poles with basal flanges), leaving a modest gap to the edge of the trap. The trap should be positioned with the wings angled out slightly.

Stretch and level the trap at the two front top corners with looped wire ties using the back tie as an anchor. Stretch the bottom fabric of the trap by placing the inner bamboo poles into the ground. The trap should be level, symmetrical, and just off the ground.  With this setup, the tension is distributed along the poles, preventing tears in the fabric or the netting, even under very windy conditions. If you can afford it, purchase a commercial octenol lure (shown hanging at the back of the trap). This will almost surely increase your catch of biting flies by a factor of two or more.
 

To provide a suspension point for the cone and attachment points for the collecting system, attach a flexible pole to the back T-bar (long enough to reach well forward and with good tension, e.g. a five foot length of 1/2 inch CPVC plumbing pipe (sold in 10 foot lengths) is suitable. DO NOT use PEX plastic plumbing pipe; it is too flexible.
 

 To finish erecting the trap, consult the options presented in suspension systems and collectors.
 

Stretchy mosquito netting may bunch up at the back of the trap as a result of poor sewing, leaving a gap to the ground. If this is the case, attach a wire loop to the bottom of the black cloth on each side at the junction with the back netting. Hook a tent peg into each wire loop and pull the sides of the trap closer to the ground.  This is not a problem with stiff mosquito netting.