Use a good backpack because it is easier to carry on and off trains. The trains do not stop very long at the station so you need to be able to carry everything you bring quickly. Nagano in winter is pretty damn cold! Warm jumpers and a good jacket will be necessary. In summer it is pretty hot like most of Japan and also humid. It rains a fair bit in Nagano so a good umbrella or rain gear wouldn't go amiss. Most things you will need can be purcahsed here. I don't recommend going to a hospital in Japan unless you really need to. In most cases the pharmacist will be able to help you if you tell them what is wrong and what kind of medicine you are looking for (a phrase book will have this in it).