Oh... Huh... Just did a search myself for that, and years ago, there were all sorts of God's-Eye loop antennas instructions out there. Huh... Not as much today, which is odd, but here's a .PDF download of one that's essentially the same thing, except this dude tilted his 45 degrees to look like a square. Either way, the same.
http://167.250.5.172/docs/Radio/Antennas/Am_Loop_Antennas_2004.pdfOh... Here's my search from Startpage results,
https://startpage.com/sp/search , when I typed-in "homebrew am god's-eye antenna loop?" I try to stay away from Google, when I can. (Hi-hi...) And, what a difference substituting that "z" for an "s" on god's. Anyway, hope that helps.