When you first start pvp'ing, the first thing you learn how to do is survive. You're not going to be able to kill many people, but you practice as much as possible on simply how to keep yourself alive (healed). Because of this, I recommend to anyone starting out in pvp, build yourself a defensive template. One that can either:
Heal quickly
Take abuse (tank)
Escape (hide/stealth)
If you want to be able to heal quickly: Chivalry is arguably the best healing method out there, but is slightly nerfed for a mage. You could do the heal/mage template (mage/med/eval/resist/anat/healing). If you play it smart, the only way you can really die is a multiple mage dump, or dismount gank. However, against a dexxer you are pretty much useless because with their high HCI and you're lack of para/disarm, they constantly hit you. In all situations, if things get rough, you run and rely on your bandages to keep you alive and no one can out damage your healing while you are running. Bandages are slow with low dex, so you'd either have really slow healing or would have to sacrifice some STR/INT.
If you want to be able to take abuse: Bushido is probably best due to evasion, but I don't know much about it. As a mage, parry mage would work well. Parry will keep the dexxers and dismounters from hitting you often, again you'd just have to sacrifice offensive firepower and STR/INT to keep your dex up.
If you want to be able to escape, stealth/ninja. Put a minimum 100 hide, 75 stealth, and 50 ninja on any character, and you can get out of virtually any situation. Its an expensive skill proposition, 225 with zero offensive firepower, but the only times you will die is when you want to, when you make a mistake, or when there's a detecter around.
Based on your current template, the easiest way (ie the shortest amount of training time) to get a pvp'able character would be to go scribe mage. 120 mage/120 med/120 eval/120 resist/120 wrestle/100 scribe, rest in focus. All you would have to do is dump bushido, and raise scribe, resist, and wrestle a combined 85 points.
Scribe mages are probably the most popular pure mage template, but they are also one of the hardest templates to play in pvp. You've really got to master spell combinations and timing.