Measure the length of the garden bed to determine the number of upright supports the trellis will require. You'll need to space the supports 5 to 6 feet apart down the length of the bed. Mark the location for each support with a garden stake or plant marker.
Drive a support post into each marked location along the row. Use a mallet to drive in pointed supports, such as wood or metal stakes, or dig a 10-inch-deep hole for post stakes. Install the supports deep enough in the ground so they are sturdy.
Wrap one end of a roll of nylon trellis mesh around the first support in the row. Secure it tightly to the support with plastic cable ties or wire.
Stretch the mesh to the next support. Pull it tight so there is no slack in the mesh. Secure the mesh to the second support with cable ties or wire.
Continue stretching the mesh to each support and tying it in place until you reach the last support post. Secure the mesh to the last support then cut off any excess mesh.