I'll share this here. These are way over size so you can cut them down for D.I.Y. They already have tie outs for a ridge line and multiple tie outs for all kinds of different setups. They are cheap and very big.

I use one like a fronky without the elastic on the bottom. Just gravity holds it down.

Used, $9.95

https://colemans.com/shop/camping-ge...sect-bar-used/

New $24.95

https://colemans.com/shop/camping-ge...ct-bar-unused/