This scarecrow -- affectionately dubbed "Balancing Bob" -- has a knack for using his noggin.
Holding the pumpkin upside down, draw or paint a face on it (the bottom of the pumpkin will be the top of the scarecrow's head).
Loosely fill two tall plastic bags with leaves and insert them into Bob's pant legs. Slip the bottom of the pant legs into boots. Attach the boots to the pants using duct tape or a needle threaded with fishing line.
Stuff Bob's shirt-sleeves and chest with bags of leaves. Attach the shirt to the overalls with safety pins.
Unbutton the top few shirt buttons, and insert a long piece of wire that stretches from one sleeve, through Bob's chest and out the other sleeve. Rebutton the shirt.
Now, in the spot where you want Bob to be (you'll need an easily reachable tree branch or other overhanging support), place his hat on the ground, then put his head in place. Have a helper raise Bob's legs while you insert the arm wires into the ground and position the neck of his shirt so that it meets his head.
Attach fishing line to the boots and then wrap the fishing line around an overhead branch and tie it securely. Finally, make any adjustments to Bob's posture so he appears to be standing on his head.