The edit button Apply style pops up the following window:
The available style options are:
•Original - Revert the style changes to the original layer that was selected
•Greyscale - Remove all color and create a monochrome image
•Invert - Invert all the colors in the image
•Opacity - change the transparency level of the layer image
•Eraser - Use the eraser tool to remove parts of the layer image
•Flip horizontal - Flip the layer horizontally
•Flip vertical - Flip the layer image vertically
•Rotate 180 degrees - Rotate the layer image 180 degrees
Click Done to accept all layer style changes. Click Cancel to exit and leave the original layer unchanged.