It can be frustrating working with text in Photoshop - especially when you want to create a new text layer that overlaps an existing text layer. With the type tool selected, Photoshop will edit an existing text layer, rather than create a new one.
There is a simple way around this though, rather than having to create the text in another area of your canvas and then moving it!
Simply hold down shift with the type tool selected, and Photoshop will ignore text layers below your cursor and create a new text layer - nice and simple!