During 2012 and ending in 2015 with an exhibition called Natures Threads, the textile art group I belong to devised a challenge whereby we chose two colours randomly and created a 6″ x 6″ textile art piece with just those two colours.
You can read more about the challenge here…
These are my pieces that I created for the challenge..

Blue Green – Applique with Free edges

Blue Green – Dyed and Opaled Cocoons and Felt to form a birds next

Blue and Green – Felt stitched and burned back

Black & Green – reverse applique with felt

Black & Purple – Lino Carving and stamping

Purple & Orange – Free form Applique

Purple & Orange – applique, inktense, shiva sticks

Orange & White – silk dyed, free embroidery, silk slubs

Orange & White – free form scrappy background, reverse applique with layered sheers and stitched edge

Yellow & White – Acrylic Inks

Purple & Orange – acrylic inks, tulle, loose applique & tyvek

Purple & White – photo transfer & stitching

Green & White – Wool and Free machinging

Green & White – free machine embroidery and reverse bobbin work

Green & Orange – Parsley pounding, inktense & stitching

Red & Orange – tissue paper, shiva sticks and couching

Red & Orange – Free motion embroidery

Blue & Red – Hand stitched embroidery floss, french knots and free machine stitching

Black & Orange – Freezer paper mandala stencil & acrylic ink

Orange & Blue – Layers and Stitching and Cutting

Yellow & Black – inktense background, scrapbook transfer

Black & Yellow – Gold Paint & spray on Fusible web folded and cut and opened out.

Yellow & Blue – Fabric and non-organic webbing