Place the trellis into the ground just before or just after planting the grapevines. The grapes will grow up and around the trellis; therefore it should placed almost on top of where the grapes are planted.
Allow the grapevines to creep up the trellis until they've reached the middle of the trellis.
Tie, loosely, the large vine stems to the middle of the trellis. Tie the vines loosely to ensure they can still grow upward and the stems can thicken.
Continue to allow the vines to grow further upward. Tie the vines to the topmost part of the trellis as they reach this height.
Tie any vines that seem to "fall" from the trellis. The ties should be simple knots that will hold the vines in place. Prune your grapevines back in late winter or early spring.