Go to your password page and request a password reset. If you’ve been hacked, your password has been changed and you won’t be able to reset it any other way.
Go to your settings page and delete anything you didn’t enter yourself (e.g., weird text in your bio, more info URL, etc.).
That should do it. If you have seen cases where the above isn’t sufficient to fix a hacked profile, please describe the solution in the comments. Thanks!