I copied the one that was here when we came but modified it a little. I made it from 4×4 fence posts which I drilled and bolted together with threaded rod. Then added the long and cross bearers.
Make sure there is a decent gap drop to the highest bearer from the crux of the log bearer. If it’s too close you will cut through it. If you can, recess the bolts to stop your chainsaw catching them. Space the X legs so that your middle cut through the closer two will cut your logs to fit your firebox.
I tend to fill the cradle with a number of logs and cut them together. Keep light stuff at the bottom and weigh it down with a big log on top, there’s less chance of anything leaping around.
With long lengths I rack it up and cut it like Stoner, sometimes while it’s still on the trailer.
Old one in the foreground, new one behind.