A twig archway in your garden can be used to delineate areas such as the transition between a patio and an herb or knot garden, or to frame a view.
Historically, archways have been used to symbolize the movement from single life to life with a partner in marriage, making it a crucial part of the wedding ceremony.
In my opinion, the more rustic and twiggier the archway, the better.
I use a long piece of re-bar, used for reinforcing concrete as the metal is soft and easy to bend.
Carefully anchor one end, and then gradually bend the other end to match.
Find more details in using rebar for crafts on this page.
Then you may have to make a pilot hole in the place you want to install the rebar archway with a short piece of rebar or metal pole and pound it into the ground for 30-40 cm (one foot, or 14" or so).
Insert the end of the long piece of rebar into the hole, then bring the other end to about 2 meters (6') away and put that in place. Once the archway frame is set, add twigs to cover the metal.
I use any kind of long slender canes such as willow or maple, starting at the top of the arch and wiring them in place, overlapping each group to hide the rebar form. See wire techniques for crafts for details.
For a much more rustic and twiggy appearance, finish off with some grapevine wound around, or twigs that have more of a rough texture.
Plant Clematis or other drought tolerant vines around the base of each leg, and watch in delight as the twig archway is covered in blooms.