Lots of questions like this explain how to programmatically create a mask and provide rounded corners to a UIView.
Is there a way to do it all within Storyboard? Jus
Yes, I use that a lot but question like this was already answered many times.
But anyway in Interface Builder. You need to add User Defined Runtime Attributes like this:
layer.masksToBounds Boolean YES layer.cornerRadius Number {View's Width/2}
and enable
Clips subviews
Results: