Help with strip mining in Minecraft

I watched a video by Xisumavoid on the most efficient way to mine but when I tried to do it for an hour it didn’t work I only found diamonds in a cave I found.

That sounds like just bad luck, I prefer cave exploring to mine but strip mining is a pretty good way, just make sure you’re on y:12 and keep at it.

Y:10 is better imo. I can pull a half stack of diamonds from a 30min-1hour mining session.