Hitckhiking is one of things cannot be lack if you are going to backpack. It's really help you to save a lot of money but nothing is sure that it's totally safe. But anyway, once you have intend to backpack ...
Digihitch (.com?) has language guides for almost every country - a page or two of translations of needed phrases for hitchhiking such as "where are you going" "please stop here" etc. So convenient