>>259401If you answered all these questions, you can start planning the trip in detail. That is, separate the route in day trips (with some leeway, plus a day for eventualities) and look out for places to spend the night and alternative routes for bad weather (mostly applies only to mountains).
Get a topographic map, ideally with marked trails (in 1:25000 or 50000) to plan your trip. Use Google Earth for detailed elevation profiles and distance information (make a path, save it, right click > height profile).
Bring the map with you on the trip. Don't bother with a compass or a gps in Europe, especially if you follow a popular trail. Everything is very well marked and you can't really make mistakes if you have a map.
You should look into joining the Italian Alpine Club if you're not a member yet. You get cheap maps, access to libraries (where you can ask for literature on your topic), and can cheaply rent all kinds of gear. Not to mention they will help you planning for your trip.
As for Gear, depending on where you sleep, whether you bring food/water yourself, and how many days you plan to go, you will need a good backpack and good shoes first and foremost.
Shoes depend on the terrain you will be traversing. Go to your local outdoor shop for more information, but things to consider are
-ventilation/breathability vs waterproofness
-ankle support vs flexibility
-stiffness of sole
If you will be walking on gravel roads all the time some simple trekking shoes are more than enough.
If you're in the mountains, will be crossing streams and boulder fields and generally difficult terrain, you need stiff soles, a lot of ankle support and waterproof boots.
As for the backpack, the most important thing is a good load bearing system - i.e. all the weight is on your hip and none on your shoulders. It's good if your back is ventilated and you can compress the backpack well. If you can take off the top lid to use as lumbar pack for day trips, that is really really useful.
