Chard with holes chewed through it. Sunflower heads pecked to bits. If that is what your beds look like right now, you need a scarecrow, and you almost certainly have most of the parts already.
Virginia from Peaceful Valley Farm & Garden Supply builds one here in about five minutes of video, and the whole thing comes down to two bamboo poles, a bale of straw, and whatever old clothes are heading for the charity bag. The only real skill in it is the clove hitch that holds the arms on, and that is two loops and a tug.
What makes a scarecrow actually stand up
The part people get wrong is the frame. A scarecrow that flops over at the waist has usually been built on one pole with the arms wired on as an afterthought. Two poles lashed properly, with the crosspiece about six inches down from the top, gives you shoulders that hold their shape all season.
The other trick is netting. It is optional, and it is the difference between stuffing an arm in thirty seconds and fighting a shirt sleeve for ten minutes. Any garden netting works.
Make him weatherproof from the start
Use waterproof paint markers on the burlap head. A regular marker looks fine on day one and runs straight down his chest in the first rain, and there is no fixing it once it has bled into the fabric.