Traveling as a grad student on a very tight budget:

You book the cheapest mode of transport with the most transits at the most inconvenient hours.

You cook your meals and eat simply and sometimes eat the same thing for days.

You rely on the goodwill of friends who let you take over their couches and shower you with blankets and feed you out of their fridge.

You trust in the kindness of strangers who help when you are lost in foreign places.

You learn to be grateful.