all magic is manipulation of symbols.
Symbols bare a meaning, meaning is a kind of thought, thought is a kind of energy, energy follows energy and energy forms the foundation of the universe. therefore, symbols shape the universe via this process.
the variables between different magical traditions are what symbols are used, how those symbols are made, what those symbols are made of, and how those symbols are invested/activated.
a particular symbol system that is almost universal is the vice, words of power and incantation.
almost anything can be used as a symbol when made/performed with deliberate intention and forethought.
make a symbol while holding its meaning in your mind, as well as your intentions to cause magic with this symbol, and you have cast a spell.
all of the senses can be used to create a symbol and fill it with meaning. the most common being sight and sound.
to lift an object up and make it into a magical symbol capable of causing change, it must b imbued with intention and deliberate meaning (read: thought energy). visualization can be one way of doing this.
most spells stack several kinds of symbol into a single unit that is then activated for the desired effect.