Here is the third swatch, in checks, in preparation of the next weaving guild meeting. The colors are what I might call wine and rose, in Valley Yarns Valley Superwash DK. The selvages look better; I just carried the yarns up one side.
I still haven't marked any vertical lines on the swatch maker. However, I am getting better at warping through the holes. My method involves wrapping the yarn around two chairs as I go, to keep the yarn from snarling. Kind of annoying but effective.
I'm still color-challenged, but I am working on it. Converting a color photo to black and white helps determine contrast. I think these two colors are okay in that department despite being in the same hue family.
One more swatch to go, in twill. That will be a bit challenging on the swatch maker, but doable. I'm getting more comfortable with hemstitching.