An Archbishop's Guide on what to consider before making a Magician character!

How Magician are you?!
Unlike a relaxed scene we see in Academy City where students run around being peaceful bags of science absorbing Esper abilities in due time, Magicians usually come from a rough background if we go by the examples shown in To Aru series. In contrast to the many Espers we see, alot of the Magicians we see are hardened veterans in their field, most have some knowledge of combat experience. A good number of the more competent Magicians ally themselves with a Magic Cabal but according to the novels we do see some casual Magicians who gather up like a fun club for activities like social gathering, fortune telling (usually love fortune telling) or meditating. So you have to draw the line what kind of a Magician you are. The more powerful you create them, likely they would have a longer history of experience and a reputation to back it up while if you're trying to go for a happy go getter type of Magician it's more than likely they'll belong to the casual groups who don't actually practice any lethal Magic, as I mentioned before the type of junior Magicians who gather up for normal highschool clubs like discussing the occults or telling love fortune etc etc. It's likely that if you're trying to create a Magician that just wants to be a normal student please take note that you're probably not going to be a Magician like the ones we see normally in the series.

Dual Skill as a Magician?
Unlike Espers yes a Magician can have this trait as long as the myth or ritual they're practicing allows it to have various forms of magic. For example let's say that you're a Magician who wields a spiritual item like the magic sword Mystelteinn, you can then say because it was used to kill a God Baldr who was said to have a magical defenses that was said to have been impenetrable by all projectile weapons, the sword is able to bypass magical defenses rivalling a Pope Class Barrier or cut through it. That's one skill you can have the other can relate to the history of the sword as the fallen branch of the World Tree Yggdrasil, the tree that bore fruits such as the Apple of Idunn said to grant immortality to the one who ate it's magical fruits, with this you can say that as long as you held onto the hilt of mystelteinn you gained enhanced regenerative characteristics that corelates to the legend of the world tree Yggdrasil.

Do I need to study Myths and Legends to make a Magician?
To a certain extent yes since alot of Magic from To Aru heavily relies on such things, it's highly recommended.

My Magician is a Sword expert!
In all honesty the swordsman thing is really rampant on both Espers and Magicians. This is more towards I don't recommend it but by all means it's not completely forbidden from people pursuing a Swordsman Magician type character if they can make an amazing character while keeping up with myths and lore rituals. Sadly I haven't seen alot of these if not ever which is why I don't recommend the combination. Swords are only really effective in the hands of a Knight or Amakusa and weapons specialist that can wield a magical sword. If you're just a Magician or Esper armed with an ordinary swords, chances are anyone with a pistol can kill you relatively easily from range.