firebolt = geos
SS = prison
those are the places that i got to wizard in job 50 it takes time ^ ^
When I made my first character (which incidentally was a wizard) I did Fire Bolt with geos. Perhaps I'm wrong, but later I've found Soul Strike in Prison to be the fastest. If you don't have gears, I think Prison is the best possible levelling for any acolyte or mage class character (heal-bombing or soul strike) since the exp is pretty good and you can just leech off other people (do some damage, let the others kill it, gain exp). You should be able to do this as soon as you have heal or soul strike at a decent level, but it'll be really hard at first since you can never get hit because a single hit from the monsters will kill you. You'll get good at hitting and running

Just go to a place where there's lots of people, often even if you do die a nice priest/hp will resurrect you if you ask nicely.
Eventually you'll be strong enough to kill things on your own, as soul strike will start to deal 5000s of damage and heal will do a couple thousand. You'll still be mostly hit and run, but you'll kill much faster. You'll also be able to sustain hits by this time, so bring meats along so you don't die if you get hit twice (but to save money try not getting hit at all). If you have eddgas, it will help since otherwise getting hit once when a mob is after you is not fun. Or just bring flywings, since you can't very well kill a mob anyways.