I would stop producing crap that stops working after 3 months just so that people would have to buy new, only to ensure the continued success of my capitalistic interest, thereby reducing drastically the consumption of the world's natural resources. Instead I would make things that last, that can be repaired and do what they are supposed to do as well as I could make it. We have the technology to make phones that will last virtually forever, construct them so that they can be repaired rather than just discarded after a few months. We have the technology, but in the current economical system it is not beneficial to do so, as anyone who did it (which would be ethical and responsible) would be out of business.
I would stop raising kids on dreams that are bound to break only to put them on medication that does nothing for them other than to make them slaves of an industry that benefits greatly from this.
I would correct the gross economical imbalances created by europeans during the imperialist period and that have been enforced by the west ever since.
I would start a massive campaign to educate everyone rather than prey on their ignorance.
I would make laws that protect people, not restrict and oppress them and protect someone's financial interests.
I would take all the resources and efforts that currently go into war and divert them to intensive research to develop free, infinitely renewable, clean energy to be distributed to everyone for free.
I would make stupidity and ignorance crimes punishable by education.
I would throw money at the Venus Project
and tell them to get serious on a whole new level.
Then I would seek to unite all humans in a joint effort to explore space, both inner and outer, in the spirit of adventure and understanding.
Since you asked.