First design you UI in wAny|hAny size class.
Now make the necessary changes to layouts in wRegular|hAny size class for iPad landscape and wAny|hRegular size class for iPad Portrait.
If that does not work out, we need to make the different layouts with code as follows.
if traitCollection.verticalSizeClass == .Regular && traitCollection.horizontalSizeClass == .Regular {
var orientation:UIInterfaceOrientation = UIApplication.sharedApplication().statusBarOrientation;
if orientation == UIInterfaceOrientation.LandscapeLeft || orientation == UIInterfaceOrientation.LandscapeRight {
// orientation is landscape
} else {
// orientation is portrait
}
}
Hope this helps. :)