Prune side shoots away from the willow branches. You should have three long willow poles when you have finished.
Tie the three willow branches together at the ends with the polyethylene tape.
Set up the branches so that each branch is spaced out to form a tripod. For added stability, bury each leg of the tripod 1 foot deep into the soil with the shovel.
Plant a lightweight climbing vine, using bean seeds, pea seeds, or a jasmine or similar plant at the base of each tripod. A heavy, woody plant such as rose canes or wisteria is too stout for a willow trellis.