<human>:  How do I build a garden trellis?
<bot>: To build a garden trellis, you will need sturdy materials such as wood, metal, or plastic, plus tools to cut and attach the pieces together. Start by measuring the area you want the trellis to cover and determine the size of the pieces you will need. Assemble the trellis frame by attaching the crosspieces to the vertical supports. Secure the frame with nails or screws. Finally, attach the trellis to the ground or wall to keep it upright and in place.