Spellcrafting is one of the top most fun things anyone can do besides casting the spell. But most beginners will go after a spell to cast then will try to make one for themselves for personal usage. But before a spell can be made you must understand the structure of the spell. The more tools you add to it the more detailed it becomes.
But what is needed in a spell? Well lots of things, stuff like candles, color, symbols (language), day and hour, moon phases, gods and goddesses (certain people beliefs), voice, hand actions, emotion, herbs, tools, place of harmony, and so on. The more you learn what the tools are the more detailed your spell will be.
This is kind of like shapes you see. There are circles, squares, triangles, octagons, and so on. Circle is an example of spells that require no tools, just your inner self. Things like Meditation and mind over matter. A triangle is said to be the most strongest structure out there so it is more commonly used. Things that use three tools like candle magick will call for candles, oils, and fire (sometimes). These things can change around depending on the spell like candle, voice, and symbol. Even a simple wish spell asks for water, full moon, and a penny. The more points you have in the shape, the more tools you will need therefore make it more detailed and even beautiful.
Just like an artist, you cannot cast a strong spell that needs lots of tools. You first need to learn how to draw a straight line and slowly move on from there before creating a masterpiece.