This is the point in time where I say I'd be a good man and donate to worthwhile causes to make our world(s) a better place(es). This is also the part where, in the stories, the one who was gifted turns evil and abuses his power. So would I be a good man?
Provided I don't go crazy from the wealth... The big things can wait. That takes geniuses with access to technology and money. It takes fresh ideas. And there's been several variations on the quote "If you have a roof over your head and a bed to sleep in you are richer than 75% of the world." I've also heard that if you make 50,000 USD annually you're in the top 1%, although I do not know if that one is true.
Assuming the distribution of people with potential, inspiration, and ideas is roughly equal, and only the ones with resources can ever advance the world, then we as a species could potentially only be utilizing 1% of our geniuses.
With this in mind I would spend most of my 1 trillion dollars on infrastructure projects in the poorer parts of the world, including large scale development of renewable energy and sustainable farming. I would also try, somehow, to make sure that population won't get out of hand. Unfortunately that money will run out quickly, it is estimated that the US highway system cost about 500 billion dollars in today's money. But if a trillion can power Africa or South America with renewable energy, then we're a big step closer to further expansion and more enabled geniuses who in turn will continue to make the world a better place.
And then of course I'd save a couple billion to donate to SpaceX so we can get to Mars soon. But tell them that they need to find a way, at least for early manned flights of the BFR, to include some sort of launch escape system.