The way I first learned the planetary associations for each day was to remember my French- Lundi, Mardi, Mecredi, Jeudi, Vendredi= Luna, Mars, Mercury, Jupiter, Venus and saturday and sunday are fairly obvious.
Monday is the day associated with the moon and therefore yesod on the tree of life. This day is great for any work involving the astral plane and psychic work. The planetary angel associated with this day is Gabriel. The colour associated with this day is purple.
Tuesday is the day of Mars and therefore Geburah on the tree of life. This day is good for any spells regarding deterring enemies or negative energy. It is also associated with spells for strength and victory. The planetary angel associated with this day is Zamael. The colour is a scarlet- the colour of healthy blood.
Wednesday is the day of mercury, it is perfect for most magickal works. However specifically this day is most suited to spells and rituals in which knowledge is the aim, also healing. This day is associated with Hod on the tree of life. The planetary angel of this day is Raphael. The colour associated with this day is orange.
Thursday is the day of Jupiter. This day is great for good luck, prosperity, wealth and general happiness. It is also a good day for victory spells in the sense that it will bring you good luck, I would state Tuesday is the better day though. Jupiter is associated with Chesed on the tree of life. The planetary angel associated with this day is Sakhiel. The colour associated with this day is a vibrant blue.
Friday is the day of Venus and is therefore the day for love and lust spells. Love can also fall under peace and friendship. This day is associated with Netzach on the tree of life. The planetary angel associated with this day is Anael. The colour is an emerald green.
Saturday is the day of Saturn. It is the day of death, that is spells which bring something to an end, banishing negativity , or ceasing a habit which is ruining your life. It is governed by Binah on the tree of life and the planetary angel of the day is Kasiel. The colour of this day is black.
Sunday is the day of Sol, the sun. It is used for spiritual rituals, rituals for praising the divine and your higher self. It is also a good day for blessing and purification of the mind, body and spirit. It is also a good day to begin rituals which will take more than one day, or spells to do with a beginning or to bring about an opportunity of some kind. This day is associated with Tiphareth on the tree of life and is governed by the planetary angel Michael. The colour of this day is gold.