storyboard positioning text below image inside a button

I've written an extension that do the works for you, Swift 4 compatible.

public extension UIButton {

    func alignTextBelow(spacing: CGFloat = 6.0) {
        if let image = self.imageView?.image {
            let imageSize: CGSize = image.size
            self.titleEdgeInsets = UIEdgeInsetsMake(spacing, -imageSize.width, -(imageSize.height), 0.0)
            let labelString = NSString(string: self.titleLabel!.text!)
            let titleSize = labelString.size(withAttributes: [NSAttributedStringKey.font: self.titleLabel!.font])
            self.imageEdgeInsets = UIEdgeInsetsMake(-(titleSize.height + spacing), 0.0, 0.0, -titleSize.width)
        }
    }

}

Where spacing is the distance between image and text.

If you are looking for output like this

1) Select button and go to Attribute Inspector in your storyboard to get this result of Button size 50*50

2) Now set Title Insets of Button