Select a dark red ink or mix a small amount of black ink with red ink. Darker ink will stand out better on brown skin. If you only have access to bright red ink, it is best to wait until darker colors are available.
Color the area of the skin with a thick, even layer of dark red ink. Use a three- or four-point needle for effective shading, and apply the ink as you would when filling in any other tattoo. Fading the ink for a detailed shading effect will result in choppy and unnoticeable color. If you must fade the red, begin with darker areas to get a feel for how the skin takes to the shade before lessening the depth of the needle.
Allow the tattoo to heal completely and observe the outcome. To make the red ink noticeable, a second pass over the tattoo and repeat of the shading process may be necessary. Do not tattoo as heavily on the second pass, as you risk scarring the skin's surface.
Wait two to three months for the second pass of color to heal and fade. If the color is still not as vibrant as your customer desires, perform a third pass with bright red ink. The third pass should be the final time you attempt to brighten the shading. Use a five-point tattoo needle and apply the bright red as light shading rather than a dark, filling color.