Nothing. If I try to do something I create the very events that create Hitler me. The Bootstrap paradox, as seen in 12 Monkeys or Netflix´s Dark. The latter find a way to create a new timeline but the hero ends up erasing his and the other doomed parallel world. Not a great outcome either, 2 broken worlds die so that a new one can live.

Edit: A deleted (but canon) scene in Terminator 1 and its recreation in 2 explains how traveling back to the past to ensure victory against Skynet exposes humanity to the tech that creates Skynet. T1 is a closed loop and T2 has an open ending that suggests that the end might have only been pushed back again. Cameron has balls. Blockbusters used to have stakes...
https://www.youtube.com/watch?v=zYkBSFKCDog
The factory in T1 belongs to the same company that will create Skynet. I wonder if the robots knew that they couldn´t truly lose.

Unless we're given some kind of proof/explanation along with this information of what kind of future knowledge this is, like if it's a closed time loop like residentgrigo said, we don't know whether or not changing the future will do anything, so we might as well try. Not all prophecies are self-fulfilling, and if it is then it'll happen no matter what I do, so my actions in the meantime are already predetermined anyway.

I'd probably go with trying to stop it from happening, I honestly don't care if I prevent some as of yet nonexistent potential happy ending for some future hero or something, I'd rather save all the lives that would be sacrificed and prevent all the suffering that was necessary to create that, plus save myself in the bargain.

If after trying unsuccessfully to change things it ultimately became clear that I wouldn't be able to prevent it, then I'd take the suicide route. I'd probably start setting up that contingency plan from the start though and be pretty careful about the method and timing to make sure I can't be saved and prevented from trying again, otherwise all my efforts would be for nothing.

Will reread "Things I'll do if I ever become an Evil Overlord" + start my memoirs beforehand.
PS: why so negative answers?

In the first place a 'villain' is a third-party perspective. There's a certain reason why people end up making the decisions they do (for example, killing others) and within ten years such decisions won't merely stem from a random series of events but from a pre-existing worldview. Knowing that you'd be seen as a villain in the future for taking action in response to traumatic events, would you really change your entire worldview just based on that? Rather, it would either be totally unbelievable, or a fitting description of a person that you already want to become.

It's not really so relevant you'd be seen as a 'villain', but rather that a series of traumatic events will soon befall you. A series of incidents that were ultimately out of your control - your relatives dying under a medical system gouged by corruption, losing your job; friends and public face due to a critical social mistake, the murder of your siblings due to gang violence – well, whatever it may be, if it is actually believable that such a thing is prophesised to happen, I think most people would try and struggle against such a fate.

Event is most likely traumatic, so i would want to stop it... Becoming villain is secondary...

Depends when I get the prophecy. I have bouts of depression so if I get it during that down period, most likely would suicide. Lol if not then I'd probably do nothing, forget about it and go on with my life. I don't think I'd try to change it... unless the prophecy was very descriptive

I go sit under the forgiveness waterfall for 10 years

This feels like one of those "do you think you can change your destiny?" questions, but I don't know why it made me laugh a little.

I'm wayyy more worried about the traumatic events themselves than being the villain. xD I guess whatever doesn't kill you DOES make you stronger...and evil. Lol.

Edited to add I picked "try to stop the event from happening"!

Let's take becoming a supervillain out of the question, if I know there are going to be traumatic events ahead of me in general, and I KNOW what causes those traumatic events, I'm gonna avoid it because surprisingly I do not want to be traumatized

Hitler wasn't the villain, but the good guy. Would love to become the next Hitler, so "Nothing".

My gut reaction was to pick "Nothing", just because trying to change the future sounds like an immense hassle and ton of work. Not sure what it says about me, but i guess world better be prepared. *shrug*

I would try to do something about it. Mostly because I can easily see myself as the villain, there are a lot of times in my life I do think the end justifies the not-so-nice means. However I'd search for better means if I knew the reaction to the original timeline, though in true villain fashion would be for self-preservation rather than any moral change.