I found a cable pattern in Stitchionary Cables that is very similar to the trestle lines. I did a swatch to see what it looked like:
At first I thought of doing a knit/purl pattern but I really like these cables. They will look great in a neckwarmer. I also played around with ribbed edging. The bottom edging of the scarf is 4/4 rib and the top is 2/2 rib. The 2/2 rib is definitely the best. My swatch turned out different than in the book, but, I think, to my advantage. It looks more like a trestle than a trellis.
I am using a merino/silk blend to make the neckwarmer. I want to give it to my husband and he hates anything even remotely itchy. I hope this is soft enough for him. This is Manos del Uruguay Silk Blend in brown. Obviously the picture below is a little washed out. The swatch is more indicative of the true color.