// Initial setup and presentation
UIViewController *sampleController =  [[UIViewController alloc] init];
// pass sampleViewController as root
HTKScrollingNavigationController *navController =  [[HTKScrollingNavigationController alloc] initWithRootViewController:sampleController];
// show "modally" using helper. (optional, but recommended)
    [navController showInParentViewController:self withDimmedBackground:YES];

// Push new controller
UIViewController *sampleViewController = [[UIViewController alloc] init];
[self.scrollingNavigationController pushViewController:sampleViewController animated:YES];

// Pop existing controller
[self.scrollingNavigationController popViewControllerAnimated:YES];

// Dismiss (optional)
[self.scrollingNavigationController dismissFromParentControllerAnimated:YES];