Possibly imagery,
buttons, measuring tape, different textured close up of fabrics, drawing, sketching, sewing kits, sketchbook scans?
These images could be carefully considered, photographed well, demonstrating their textured and appear more interesting and contain more depth.
If there is a colour that runs throughout the book, then the images could relate to the colour (e.g yellow for measuring tape, yellow shades buttons etc..)Cover Idea - could a close up shot of fabric? or a sketchbook illustration work as an effective colour. Possible washed out, with text over it?