String, duct tape (optional/might not be necessary), scissors, a nearby cornfield would be useful, a branch saw would also be useful...
Step 2: Get the cornstalks
You can either cut or pull the cornstalks out of the field, cutting them would be easier, and i would suggest using a branch saw.
And stand them up next to each other.
Step 3: Tie them together
Cut 2-3 6-10" pieces of string and tie the 3 corn stalks together at the top, middle, and bottom. I tie them together around the leaves so that you can't see the string.
Step 4: Put them up!
Put them up!!! I usually put them up by our a mailbox, by the corners of the house, and by the telephone poles in our yard.
You can use the string to tie them where you want them or you can use duct tape