Characters in SpellMaster are more similar to characters in books or movies than in a typical roleplaying game. There are no character sheets and no descriptions, unless you want to make one. A character is really defined by the narrative. If you want to establish your character as a good-looking, tall guy in silver-and-red clothes, simply weave that into the roleplays you write about him.

Abilities and knowledges are yours for the taking as well. Give your character what you consider appropriate so that he matches your vision. There are no character points for these things, and no experience points - if the narrative gives your character new knowledge, simply use it.
You can not, of course, take things from nowhere. Any new skills or abilities have to be narrated - you have to explain where they suddenly come from.

There is one exception to all of this, and that is magic. As magic does no longer flow freely through the world, access to magical powers is subject to rules and limits. This affects all skills relevant to the art, as well as formulas, casting and magic duels.
These magical skills are controlled more strictly in the game. Also, these values will be tracked by the game. Everything else, you should keep track of yourself.

What you should do, is put some thoughts into three aspects of your character that will be important for your roleplaying. Others will as well, so write down some notes on whatever comes to mind. However, experience tells us that you should definitely have some answers for:

Appearance

What does your character look like? How does he dress? Which unique features does he have?

Background

Where does he come from and what is his heritage? Where his parents farmers or nobles, was he raised as a priest or as a criminal, a warrior or a merchant? What, if any, education did he receive? What religion does he follow? What about his family nowadays (please, the "I'm the only survivor" story is way overdone)

Magic Style

Even if he is just beginning, do come up with a style of magic for your character. Does he draw runes, sing magic chants, write down scrolls? Is his magic flashy and visible or subtle? What kind of requirements or limitations does this bring with it - does he need his hands for gestures, his voice for speaking or singing?