When you're home you have everything at your fingertips, or at least you know where to get it. When traveling, things are a little different. You cannot take too much with you because you want to have as little baggage, you cannot even overtake all the more or less limited situations in which you will be put or you will never know where to go you get the seemingly trivial things you'll need.
I have traveled in many ways so far and realized that if I take a few essential things with me it will get rid of many beatings, so I said to make a list of them to help you. I'm not telling you to take them all with you, and surely some will be dubious. The list is indicative and can serve as an inspiration when you go on a long trip, preferably longer.
Here's what I'm trying to take with me especially when I leave with months :))
A USB stick - It's good to back up your laptop data when needed, put the papers you need to print (airline or train tickets, vouchers, etc.) and take your music or movies recommended by the people you know on the road.
A Sleeping Bag - If you are traveling in the backpacker style you will also come to hostels or hotels where lingerie is more dubious. Sometimes you will go to buses where the AC is given the maximum or in trains to the bunk. In these cases it is good to have a very slender sleeping bag in your bedroom to sleep in. In the absence of one, in India, we improvised. I bought about 5 meters of thin material and went to a tailor where an Indian sewn it in a sort of sleeping bag. Now I take it with me everywhere and it's useful many times.
A microfiber towel - These towels are much smaller than cotton towels, absorb more water and dry faster. You find such towels at Decathlon, for example.
A smartphone or tablet - Sure, it seems obvious to those who do not share the smartphone, but I met many people who were traveling without one. Even I've done it for a long time, but now I realized how useful it is to have a mobile device with Wi-Fi and GPS. If you do not have one with you yet, get it. You can use it to search for information, access Google Maps or Google Translate, search for accommodations, airline tickets, and talk to home guests. And to lose time on Facebook ...
A small flashlight - There will also be situations where you do not have the light in the room, when you want to read on the train or when you go back in the darkness from the beach and then a small flashlight will be extremely useful. Besides, it does not take up much space in your luggage.
A locker - I try as much as possible to lock the luggage with a locker. Sometimes it turns out to be useful to lock the hotel door or secure your luggage on the train or bus.
A pocket knife - It does not have to be an extremely complicated pliers and I know what. A small knife, scraper and possibly scissors is very useful in many situations.
An FM modulator and a car charger - For the moments when I rent a car and I realize that on the radio I have nothing to listen to and that the phone is downloading because I intensively use the GPS.
And most importantly, the camera - because you want to immortalize the most beautiful moments. I own a Nikon D3100 which I am very pleased with.
Pay special attention to your travel bags! It has to be a handy, useful, comfortable traveling bag.