[*Disclaimer: This is my personal suggestion, not from staff's side :3 ]
So the basic things to create a magician is to choose Intelligence specialization first as your primary/first specialization, that, if you want Magician to be the main role of your character. After that, you need to choose what type of magic that you want as your starter element. The example of available element can be accessed
here. Remember, you start with single element of magic but you can get your second magic type at B-tier and also get your third at Omega-tier. You also need wand/staff as a medium to channel your spells ^^
As for the second specialization, you can unlock it when you reached B-tier. Let's say you choose Dom as your 2nd spec
(Like Noir! Yay!), you can work on the required WC to get it without need to change the Intelligence spec.
The advantage of having Intelligence spec as your PRIMARY are, you are protected by borg and also able to see the flow of the rukh. You also able to create combination magic once you have 2 magic types at appropriate tier which will allow you to add passive damage in it.
The disadvantages are: you are not able to have defensive spell and if after you get another spec and want to add defensive skill (let's say you choose your Dom beast to have defensive role), you wont be able to have a defensive skill that is higher than B-tier. Another disadvantage is as written below:
From spec system for INT wrote:
All primary intelligence spec users must start out with weaker bodies including those of races with innate strength boosts. All Magician's are limited to D-tier damage with their bodies. The exception is if they gain Strength specialization as a secondary or tertiary specialization, in which case their abilities deal damage as normal, with the exception of the Imuchakk, who would deal damage as though they were a halfling of that race.
Hope I dont misunderstood and hope that is helping~ ^^