Use Google Maps. It will tell you when you're approaching a turn. eg. "In 600m turn left onto Main Street North... Turn left onto Main Street North".
I've been using iPhones for years and I've never used Apple Maps. I heard too many horror stories when it first launched, and although I have no doubt that it's MUCH better now, I've never had any reason to not use Google.
I see; perhaps it's time for a change. I've stuck with Apple Maps since I haven't had any issues like those horror stories we've heard, and the automatic integration into the rest of iOS is useful. But more intelligent directions wins.