The book she gave Raafi has three sections, going into detail about the process that Scyelen explained to him at lunch.
Keying. This is an innate ability and a basic action. It is binary. Either a mage can key to an element or they can't. Actually gathering the ambient will of the world using your keyed element is a highly subjective process described in far more flowery than technical language, but it becomes second nature with practice. It is widely agreed to be the easiest part of casting, which is only proper, since this is the essence of the Founder's Gift.
Evocation. In contrast, this step is highly technical, requiring mental focus and adequate understanding of one's own intent. A mage's Element(s) may be thought of as one of these several metaphors; like a container with a shape of ideas rather than forms.
Willpower. Once a form of ideas is embodied in a mage's Element, the mage temporarily offers up some amount of their capacity to bend reality to their cause to fuel the transubstantiation of the ambient will within their Element into physical reality.
Overall, the book was clearly written by someone reasonably intelligent and competent who had some idea what they were talking about, but had never dreamed of the scientific method.