I'd donate Money and Clothes to the people who needs it.
I would do a voluntary Work , which would help the poor.I'd make campaigns.
I'd try to stop the global Warming.However, it's impossible . I'd convince the USA to assinate the Kyoto's Protocol and stop the Pollution.
I'd Create and campaign which would incentivate the recyclation.
Stop the factorys polluting the ocean.And stop the deforestation and incentivate the govern to Reforestate.
And Also Stop The war that Kills more than 1 million of people per year.
So.. change the world