You really do not need any notification before a turn. Trust me on this and yes, I am VERY much like you and used to get lost all the time and such before I bought my gamrin. The only time I use the notification is when I am on long rides and I need to be tapped into one of the other pages of the garmin like for HRM, or cadence, etc. But when I commute or are on rides that I am scouting out, I use the map function. I just look down when it is about time to turn. No worries..... it works 100%
I will note one thing, even if you want it to tell you where to turn, you still need to do some up front work. Yes, the edge will tell you where to turn but it happens RIGHT before a turn. If you want it to notify you like 200 feet out before the turn, you have to load it into bikeroutetoaster.com and set it up that way. It is an easy process and I can walk you through if/when you need it but really, if I use my garmin on tour, I am using the map function. It is as simple as that.