Question Regarding Photoshop/Brushes

I don't understand how I can add these to my sigs. I mean, I know how to add them to my "library of brushes to use" but I do not understand how to "integrate" them into my sigs.

So far I have been just making a few copies of the render and then blurring them and so far it has been working out pretty well.

So I guess my question is, how do I make my sigs look cooler with brushes?

I have looked at some tutorials but they don't really explain it to me very well.