I think the biggest expense will be hotels or hostels. For three months I reckon you will spend somewhere in the region of 600-700 euros at least for housing…depends though on how long you stay in which city, where and when…
My advice is to stay on the outskirts of cities, where hotels are cheaper. I usually book at http://www.venere.com/italy/rome for Rome hotels or use venere.com for Italy in general. As far as food goes that will be pretty cheap and I think you should consider like 400? Depends how much your budget is really! - written 5 months, 2 weeks ago