High fluency? I think you need to specify exactly what you mean by that. Do you mean primarily speaking and understanding or also reading and writing? I myself live in Spain and have my Spanish at a rather comfortable B2 production, C1 understanding, which I would call high fluency myself. This kind of level wouldn't be necessary for travel though. I understand pretty much everything, from TV series, lectures, novels, up to books about philosophy. What is needed for travel is substantially less - even TV series are harder to understand than people talking directly to you. Getting by in every day situations and even having not so bad conversations can be done comfortably with B1 already. For university level education my production would still be a little low even at B2, especially my writing skills, and it sometimes tends to be a little frustrating for me too, because I still make mistakes, but it's more than enough to live here. Be clear about your goals and then work towards them accordingly. B1 which is still intermediate is enough for travel. It's comfortably reachable within a year. If you want to reach B2 and high intermediate borderline advanced you will have to study much harder. High fluency, as in B2, would likely take some 600h, which would be a bit more of 1 1/2h of focused work each day. That's a lot to keep up for a year!
A good method for your goals is also necessary. To reach my level of Italian of A2 (certified, actually) I needed 3 months of 3h+ a day working through a whole university level textbook and workbook heavy on grammar. The method was all wrong for actual conversation though. It was mainly grammar torture and didn't prepare me for speaking at all, well, at least not beyond "Where is the train station?" and "A coffee please" or "I like dogs, but I don't like ice-cream". And usually I wouldn't understand the directions given when asking for them. However, after the course I read the first Harry Potter book in Italian without a dictionary, although the literary past tense wasn't covered in the course. A few years later after I had abandoned Italian mid-stride before becoming functional (too much grammar torture), I realised that I could somehow understand everyday conversations of my Italian flatmate who was from the north. However, I usually can't understand movies, people from the south and I could never speak. Lessons you should take from that is to forget about grammar and focus on the skills you actually need, understanding and speaking. Also prepare specifically for the region which you will be visiting - in the south you will need the literary past tense a lot, so focus more on reading and audiobooks. In the north you might only need to read in the beginning, unless of course you enjoy reading.
If I were to start Italian from scratch now with a focus on actually using the language, I would start like this: Assimil - Italian with Ease, while doing Duolingo and watching a cartoon with 20min episodes I know from very early on, after like 5 lessons of Assimil. Simpsons is good. Don't worry if you don't get it at first, usually you don't need the dialog to understand what's happening in cartoons and you will quickly start to understand words and then full sentences here and there. As soon as I'd be able to understand children's stories with a dictionary I'd also start reading books to expand my vocabulary. I like Harry Potter for that and it's usually the first book I read in any new language I learn. You might think that reading isn't really necessary if you have a focus on speaking, but it's actually the only way to pick up new vocabulary fast as long as you're still not understanding the spoken language well. As soon as you do understand spoken language and if you're not visiting the south, you might want to drop the reading and binge watch series instead, because it's better preparation for the kind of language you'll encounter in everyday situations. Start with dubbed series that you know already, first with subtitles, then without, finally move on to series and movies produced in Italy to pick up on slang and a more natural way of speaking. All of this will get your understanding up to speed. Speaking is another issue altogether. I know people who can understand everything and don't speak a word, so it will need additional work. It doesn't come "automatically" or from doing a little Pimsleur (in fact, I don't like Pimsleur myself, too slow in comparison to other methods). Once I'd finish the passive wave of Assimil I'd do the Michel Thomas course myself and then start speaking on skype with italki, 2 or 3 times a week. After MT and the active wave of Assimil I'd also start with the Advanced Assimil, but for Italian it seems to be only available in French. Lacking that you will have to consume a lot of native material, speak, read, watch series, have fun (oh, how terrible
). Also, you might need some grammar books to fill in some of the gaps at this point, unless you don't mind making a ton of mistakes. Being fluent doesn't necessarily mean that you have to speak well. You can skip grammar and writing entirely and will get by splendidly. People will treat you differently though if all your mistakes make you sound like a 5 year old.