I do a lot of applique and I use quilting thread for back basting and YLI silk thread to applique. I have, over time, purchased many colors but the one I use the most is 235 which is a medium beige and sinks right in and fits most colors. I basically use earth tones so the 235 works for me. I you use more pastels there is a light beige that would work. When I found back basting and needle turn applique, I found my niche.