Change page in PageViewController from a page inside the controller?

I have a UIPageViewController that has 3 pages. How can I switch to a page that is within the UIPageViewController on a button tap? (Each of the pages are a separate UIViewController that I made in the storyboard).

I've tried a lot of code but I keep getting errors as I made my UIPageViewController inside my storyboard and I set it up like this:

PageViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.dataSource = self;
    self.navigationController.navigationBarHidden = NO;

    [self setViewControllers:@[[self.storyboard instantiateViewControllerWithIdentifier:@"Main"]] 
                   direction:UIPageViewControllerNavigationDirectionForward 
                    animated:YES
                  completion:nil];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    if ([viewController isKindOfClass:[NavView2ViewController class]])
       return nil;

    return [self.storyboard instantiateViewControllerWithIdentifier:@"two"];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
    if ([viewController isKindOfClass:[NavViewController class]])
        return nil;

    return [self.storyboard instantiateViewControllerWithIdentifier:@"one"];
}

via Chebli Mohamed