A friend asked me to do a tartan pillow using her choice of four colours of fine wool. My first test was a gamp (trying every colour with every other colour). I knew nothing about tartan except that the same pattern of stripes is used for both both warp and weft and it is often woven as a twill. There are thousands of tartans. I was at a loss to design my own, so I found a four-colour tartan and copied the proportions. I applied my friend's colours to it and made a "tartan ruler" as a way to chart the warp and weft.
From doing the gamp I realized that a full sized pillow with such fine yarn in pin weaving was going to be too daunting. I proposed a checkerboard sampler of 16 squares so that I can work small and modular. Eight squares will be tartan, and the other eight will be a two-colour twill. That way I can experiment with moving the design around on the tartan pattern and try a lot of different twill patterns.
I'm nearly finished the fourth square and find them relaxing to make.