This is a superb ride, few things from my experience….
Maps. We had a garmin and also the paper maps I bought from IMBA. I am glad we had the Garmin, it just makes it a smoother ride without stopping a lot. But I would say there are only a couple of points where it is tricky.
Food/Drink. You need to take a day’s worth with you each day. On some long sections, there are no shops, that’s the beauty of the route. Also obviously a full tool kit. (We had to rescue a trapped sheep with a Gerber!)
Stream. There is a water crossing at one point, so some dry socks may help!
Accommodation. We took the list with us and phoned ahead on the day depending on how far we had travelled. I don’t think there is a lot of choice en-route.
Good luck