Bunch the twigs into groups of four to eight, depending on the desired thickness of the arch. For a thin arch, use bunches of four twigs each, for a thick, large arch, create groups of eight. The bunches must be composed of an even number of twigs.
Separate the first bunch into two equal groups, group one and group two.
Place the top edge of group one twigs in the center of the length of group two twigs.
Wrap the wire tightly around the two groups of twigs 2 inches from the edge of the twigs in group one. Twist the end of the wire to secure it and push the end downward to hide it. Clip the end of the wire with wire cutters.
Create another bunch of twigs and secure it with the wire as above.
Connect two bunches, matching the top edge of one bunch with the center of the other, and secure it with wire. Bend the bunches as you connect them.
Continue to create and connect bunches until the desired length of the arch is reached.
Wrap the arch with wire, creating a spiral with the wire, with each spiral 1 inch apart. Bend the arch into shape as you wrap the wire.
Drench the arch with water and allow to dry.