This was inspired by a member on the Facebook Pin Loom Weaving Support Group who made some mistakes in her plain woven square.
This is a fun kind of pattern to weave since it shows up by “not weaving.”
R4: P16, U2, P9 [Needle will be sliding* through the warps rather than actually going Over and Under], U2, P2
R8: P2, U2, P9 [Slide* needle as in R4], U2, P16
R12: Rpt R4
*Slide means that the needle slides between the warp layers rather than going Under the L1 warps or Over the L3 warps. The L4 weft thread will be in between the warps alongside the L2 threads on either side of it. When I count the slide stitches, I tap them with my needle to keep track of them.