Make blue paint darker by tinting it with black paint; adding a color to another color to create a variant of the second color is called tinting. Black darkens the paint. Both the blue and black should be the same kind of paint--for example, mixing acrylic and tempura paints won't work because the mix will not dry correctly.
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Things You'll Need
Blue Paint
Paint Brushes
Tablespoon
Paper
Black Paint
64 Ounce Bowl
Step 1
Pour blue paint into the bowl. Fill about three-quarters full.
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Step 2
Dip the tablespoon into the black paint and fill. Pour the paint into the bowl. Do not let the tablespoon touch the blue paint in the bowl.
Step 3
Stir the black paint into the blue paint with a clean paint brush. Mix the black paint into the blue paint so there are no black streaks.
Step 4
Wipe a streak of the tinted paint onto a piece of paper to see the color. If you want the paint darker, repeat the process with another tablespoon of black paint.