Mix equal parts of cyan, magenta, and yellow to make a dark neutral (black/near-black)
Add more of the darkest pigment (or reduce brightness) until the mixture turns black
For paint, start with a very dark base (black or dark brown/blue) and deepen with small amounts of complementary colors
If using acrylic or oil, use a small amount of black pigment and adjust with tiny additions of blue or brown to avoid a flat gray
For ink, combine black ink with a small amount of another dark ink (blue/green/brown) to deepen and reduce greyness
For markers, layer dark colors (dark blue or dark brown) and finish with black layers
For colored pencil, press lightly first to build depth, then layer black and burnish
For digital color (RGB), use R=0, G=0, B=0
For digital color (HEX), use #000000
For digital color (CMYK), use C=100, M=100, Y=100, K=100
For fabric dye, use a black dye formulated for the fabric type and apply per package instructions
For hair dye, use black hair dye and follow developer/timing instructions exactly