Note: this is not shadow weave. It's a treadling option I learned from Barbara Miller.
Pattern and tabby
You may weave tromp as writ or rose fashion (Issue #8). Use tabby for the pattern thread and the pattern thread for the tabby.
Or use Mary Snyder's method.
Pattern and tabby (2)
Use 2 picks of tabby between each pattern pick in a finer yarn, one as the warp color, the other in a contrasting color; this should be a good contrast with pattern color.