Along with the lunar sign, the day of the week that one chooses for spell casting can affect the spell's results. Plan your spells out in advance so that you don't accidentally miss the best day. While other factors like the sorcerer's state of mind are more important to the chances of a successful casting, casting on the right day enhances the spell along several different lines.

As many other signs, the waxing and the waning of the days (in this case, the sun rising and setting on that day) hold significance with regards to the event. A rising sun signifies a strengthening influence, used to create what does not currently exist or strengthen what currently does. A setting sun represents fading influence—use the setting sun to remove obstacles to what you want to strengthen. In a healing spell, the waxing sun serves to strengthen the body, while the waning sun weakens the influences of bad fortune and infectants.

The days of the week were originally connected to the elements and planets, and even today calendars all over the world use the same system (though the origins of many of the day names have been lost).

Monday is the day ruled by the moon. It is the best day for carrying out rituals based on fertility, especially female fertility. Set festivals that celebrate a woman's relationship, strengthen bonds of friendship, or banish strife, during this time.

Tuesday is the day ruled by Mars, or the element of Fire. Associated with Ares, it can ensure success of military operations. In peacetime, it aids in spells to banish fear during the waning period or strengthen one's resolve during the waxing period. When strength of the mind and body are the primary concern, favor Tuesday.

Wednesday is the day ruled by Mercury and the element of Water. The Greek god of Hermes the Messenger is aligned with this day. As such, most spells associated with travel and communication are best cast during this time. Use your magic during this time to rid yourself of writer's block, or encourage a positive reception to an idea or a manuscript. Or use it for divination spells designed to acquire knowledge.

Thursday is the day ruled by Jupiter, and the Eastern element of Wood. It is also related to fertility in general and male fertility in particular. Set aside Thursday for spells related to virility, job hunting during the waxing day, or seeking a raise during the waning day. Personal ambitions, whether in business or elsewhere, are best undertaken on a Thursday.

Friday is linked to Venus, and the Eastern element of Metal. It has a powerful influence on spells designed to affect love and lust. Spells cast during a waning Friday are designed to break down barriers to love and friendships. It can also be useful for banishing unhappiness (during the waning period), or finding new friendship (during the waning period)

Saturday is govern by Saturn and the element of Earth. Cast spells during this time that are designed to increase the size of harvests, as well as affect the fertility of animals and livestock. Spells that protect the hearth and home are also best saved for Saturday. Psychic attacks and defenses are especially potent during this time, as are spells that are designed to communicate with the spirits of nature and the spirits of the departed.

Finally, Sunday is the day ruled by the Sun and the god Helios. Spells cast on Sunday are designed to increase wealth and general prosperity, especially during the waxing period. It can also support attempts to make peace and increase chances of success.