Color Coordination - Which Color on Which Day of the Week

Monday - Ruled by the moon. White, Grey or Silver, the color of pearl.

Tuesday - Ruled by the planet Mars.  Red or Pink, the color of Coral.
Wednesday - Ruled by Mercury. Green, the color of  Emerald. 
Thursday - Ruled by Jupiter. Yellow or Gold, the color of the Yellow Sapphire.
Friday - Ruled by the planet Venus. White, the color of Diamond.
Saturday - Ruled by the planet Saturn. Black or Blue, the color of Blue Sapphire.

Sunday - Ruled by the sun. Red, Orange or Yellow, the color of Red Ruby

On special days like Ekadasi,  Red or Pink. 

On Full Moon (Purnima), White.

On New Moon (Amavasya), Black or dark colors.