The documentation is being updated. There may be incomplete sections.
Switch the Apex node to Slant mode and adjust the A/B settings until you have a shape that looks pleasing to you.
Duplicate the node and attach it to the Apex node. In the second node, change the Angle to 90 degrees.
Add a Displace node to the end to warp the shape a bit.
Experiment with different A/B settings and angles to get different permutations.