Probably the cheapest way to move around, though this is not recommended for woman travelling alone. An effective way for getting a free ride is to smile, at the same time look weary and desperate (You probably win yourself an Oscar for this). Target trailer drivers or truck drivers, you stand a better chance, as these are the people who don't really mind giving rides to travellers. Ask the driver politely if you could hop on for a ride, they probably say yes if they are travelling towards your direction.

Always say something nice or offer a small gift to the driver to show your appreciation before getting off the vehicle, you might not know, you might one day see them again when you do another hitchhiking.