I like your determination in wishing to do something that's worth for you. Fund raising is not an easy task. People want to know there is a good reason behind it and normally help when they see tangible end results, as if it is a proof their money is going for a good cause. For example it is not enough sending money for a needy cause unless it is shown that the money will buy some equipment or build a school / hospital, etc.
What I mean here is be specific. Say what the money is for, let's say train tickets, travel equipment, etc. Everyone knows the worth of material things and so can sympathise... well at least this is my idea! I hope it is of help.
Good luck with your cause and enjoy the trip.