One of the things that I think many practitioners don't pay a lot of attention to is the idea of "Earthing" a spell.
Earthing is the act of bringing the magickal creation or working, which is created in the mental and spiritual realms, down into the material, to make it real.
In a sense, every act of ritual, every spell that is voiced, is part of the process of Earthing. Until you speak, or act, or move, or create in a way that is connected to your working, it exists only as potential. But I say it is important to understand Earthing, so that it can be done as a conscious act of will, rather than as an aside.
When you know that the act of earthing is happening during your working, and when you deliberately perform your working with this in mind, you are adding an extra layer of affirmation, and extra layer of direction to your work. You are consciously directing the energies of your working to where they can manifest in the material, rather than merely hoping or assuming that it will be so.
One of the things that is a repeating theme in magical workings, are the ideas of the "law of sympathy" and "the law of contagion". Alongside that, there is the idea that a magical working (a working in the spiritual realms) must be "earthed", or brought down into the material world, or connected to the material in some way.
Among some Native American nations, when someone had an important dream or vision, having the vision was only part of it. In order to actually make the dream's medicine real, it had to be brought down into the world, by having members of the nation or tribe act out the events in the dream (often wearing costumes, or doing symbolic dances).
When you do a magical working, you start with your intent, but you also may light a candle, or say a spell or prayer, or make and use an amulet, or perform a ritual. This is part of the "earthing" process. You choose the candle's color (or even ingredients), or the spell's words, or the amulet's composition, or the talisman's design by how those things are _associated_ with what you are trying to accomplish.
For instance, people might use a green or gold candle for money or success, white for cleansing, black for banishing, red for passions or energy... etc. They might call on gods or spirits or helpers in their spell, based on either that spirit's connection to the person, or their association with the kind of work (Odin for wisdom, St. Theresa of the Roses for miracles, Aphrodite for love, etc.).
When you do these things, you are attempting to invoke the laws of sympathy and contagion. You are attempting to cause like to attract like, and for to cause things which are connected in some way to act upon one another, even at a distance.
When part of your act of creative will involves bringing your spell consciously into the material, you are adding a special ingredient - you are creating a connection between what you desire, your actions, and the world around you. It is important that you not leave this part of your working in the realm of ideas. You must bring it from the realm of ideas into the physical world.