How to creating a button with a symbol on it

Choice 1: creating a button with text is easy. The text provides the visual meaning and the underlying image can provide simple feedback for hover and push.

Choice 2: creating a button using images is conceptually simple but laborious. It's all done with images, no text.

I'm looking to produce a button that looks and works like a text button, but in which the text is replaced by a symbol.
Choice 3: a Unicode character (like an arrow) but I can't see how to do that with text.
Choice 4: use a simple transparent PNG instead of Text, but I can't get that to display at all.

So: how to produce a button with a symbol, either a Unicode character or a single, simple image, like this one.

 

If all you want is a button with an image on it, either you make the button custom in an image editing program or you create a new button and instead of the text as a child of the button, you add an image as the child of the button. Then just put the image at position 0,0,0 to center it on the button and adjust it as you'd like.

What issue are you running into with either method?