This is something I have dreamed about doing...but how does one financially do this? I'm still in college so sorry my naivety. It just seems that it would be in

This is something I have dreamed about doing...but how does one financially do this? I'm still in college so sorry my naivety. It just seems that it would be incredibly expensive to embark on such a trip. And I completely believe it's worth the cost but still, how do you determine when you have enough to embark? And beyond just visiting all the countries, I would like to incorporate service into my travels. So for every country that I go to, I would like to do community service there--anything to help the underprivileged but specifically help in making sure people are properly nourished if that is a problem. I know I can't save everyone, but I do want to do some good while having fun.