I'm a big fan of concrete reinforcing wire, which may be what black thumb means by concrete mesh (different parts of the country, different terms for the same thing, probably). I prefer a 6 foot length because that makes a 30 inch diameter cylinder. I also put one stake inside the cylinder and use twist ties to tie it to the edge - this prevents the cylinder from blowing over due to storms, especially later in the season.
Here are two relatively poor photos to illustrate what I use (been using this setup since at least 1990):
When you cut the six-foot length from the roll of mesh you buy, leave the cut pointy bits attached, then fold them over to connect the cut section into a cylinder:
These things last for decades!
In case anyone is interested in the blooming plant in the background, that's golden alexanders (Zizia aurea).