Daron closed his eyes not to sleep, but to recall the fireball spell, which was also the first, and only spell he knew about.
Essentially, there were three steps to casting the spell. The first one was to construct the spell matrix in your head, which was actually the part that took him the longest to get correct, since there were 2 symbols, and he not only needed to learn them, but also know their meaning, and then put them all together in the matrix to actually form it. The two symbols here meant 'Heat' and 'Fuel'. Although their meaning was extremely simple, learning the shape of the symbol was what was complicated, since there were countless lines going in seemingly random directions. If you got even one of the strokes wrong, the entire spell would fail, and the caster would face backlash, ranging from headaches for low level spells, all the way to death for the high-level spells.
Unfortunately, Sirious could not help in this aspect. Sirious was connected to his sub-conscious, while casting magic was related to the conscious side of his mind, making it impossible for Sirious to meddle in, or help. The only thing she could do was project the matrix into his subconscious, achieving an incredibly weak version of muscle memory for his mind.
This allowed Daron to more easily make the symbols. However, it still took a long time to learn the symbols, and the muscle-memory trick only worked after he had successfully learned all the symbols.
The second step was to inject your mana into the spell matrix. This was the easiest part, and also the part that cost mana.
The last step was the project this matric to the outside of his body. This step, according to the book, was actually supposed to be the hardest part, since the person needed to extend the influence of their mind outside their body, relying only on their own imagination.
However, for Daron, it was actually almost as easy as the second step. Sirious attributed this to the incredibly large subconscious that Daron naturally possessed, saying that the power of one's imagination was linked to how well they could depict something in their subconscious. The larger it was, the more detailed the imagination.
And just like that, a flam appeared above Daron's palm. However, this ball of flame about the size of a golf ball would only last for 10 seconds. If he wanted it to last longer, he had to inject another point of mana, which would last for another 9 seconds. If one had enough mana, they could still not make the fire last forever, since this spell had a limit; 55 seconds. After that, no matter how much mana you added into it, it would diffuse into nothingness.
There were also other problems with extending a spell, and that was the once he caste the fireball, it would last 10 seconds no matter where it went, or how far it went. However, to resupply it with mana, he needed to be within 20 meters of the fireball, a rather close range if you wanted to use it in combat. Another issue was the fact that Fireballs could, when launched at the optimal angle, only travel a distance of 30 metres. And this optimal angle was naturally not flat, therefore creating a long and beautiful, yet clearly visible arc in the sky, so as to act as a signal for the enemy to dodge, thereby making it useless as a sneak attack from a distance.
However, this was not relevant to Daron, who only had 2.1 mana within his body, barely enough to caste fireball twice, or make a single fireball last for 19 seconds.
Sighing, Daron closed his hand within a second of constructing the fireball, and bulled back 90% of the mana that had been placed within the fireball, allowing him to still hold a total of 2 mana, with the last 0.1 being filled up slowly.
Naturally, in an environment like this, he still needed to keep his mana up, since his natural rate of recovering mana was only 0.1 mana every 2 minutes, meaning he needed a full 42 minutes to recover all his 2.1 mana if he fully exhausted himself.
The only problem with this method of casting which actually affected Daron was the fact that over time, as long as he did not practice the spell, it would be forgotten from his memory, and he would have to go back and read through the book again. Therefore, he had to practice any spell he wanted to remember at least once a month in order to remember them. The reason for this was apparently the fact that humans are not meant to wield the power that belonged to the high-elves, and therefore the world of mages, would try and expel the very mages that protect it.
With his practice done, Daron closed his eyes and finally went to sleep.