The most important thing to keep in mind while planning your vacation is to keep yourself flexible!! Trains and buses are late, money can run out, and chances are you'll change your mind once you get there. Keep a very general idea of what you want to do and see in your mind.
You'll probably end up meeting people along the way and teaming up with them and learning about different places you hadn't heard of before. The first time I went backpacking I had this in mind - do a circle. I landed in Germany and had to depart from Germany a few months later. So I went north, west, south, east, and back west to Germany. A great trip. There were many cities that I wanted to see that I didn't get a chance to, but I saw many many more things than I had ever thought I would. I met many people who I travelled with for a few days at a time, and I met people who invited me to their home countries to visit.
Manage your expectations. Don't hammer out a plan and say "I'm going to be here for three days, then move on to here and spend a week." Keep your schedule rough and open to change. That's all part of the adventure!
I'll be adding more tips and advice soon!
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