I learned mostly with a “close enough” approach to navigating the city. I learned the main drags through and near the center of town like Mass. Ave., Huntington, Boylston, Comm. Ave. Beacon St. Stuart/Kneeland, Congress, State, Tremont/Cambridge, Atlantic Ave., etc. Generally speaking, almost anywhere I was going in town was within pretty easy walking distance from one of those streets. So I’d find parking along or just off that main drag closest to my destination and walk the rest of the way. Eventually, I came to know a lot more of the secondary and side streets. But that part took time and experience (and many wrong turns).
Boston’s a hot mess, but it’s small and compact. I think newcomers are surprised at how small it can feel once you start getting an idea of how close things are to each other. So if you’re OK with parking a few minutes walk away instead of fretting over the exact lane or alley your destination is located on, it’s a lot more manageable. And getting turned around on foot is a hell of a lot more forgiving than in a car.
I also did the Mapquest thing in the early 2000s (when I learned to drive). Especially for trips to outer/unfamiliar neighborhoods. But most of my driving was based on proximity to nearest surface artery as trying to read a printed map while in traffic on crowded Financial District Streets is not advisable. Today, Waze is almost always on to help avoid backups due to accidents, closures, construction, etc. Not so much because I don’t know how to get from A to B.