There is no best color. Different light conditions have better combos. I use at least 3 colors on a wing. Mine are usually a bright color, a dark color and a contrasting color. The 2nd and third are usually smaller. I also put a strip or two of chrome or gold foil on the leading edge, about 4 inches by 1 inch and it blinks when the sun hits it. If you loose it, it helps find it quicker.