Update free_skymaps.adoc

Cleaned up Gimp instructions.

src/docs/asciidoc/jme3/advanced/free_skymaps.adoc

@@ -102,18 +102,18 @@ You can use link:https://www.gimp.org/[Gimp] to create SkyMaps from a single ima
 
 After installing the scripts you open a image in gimp. This script works by slicing up the image into 6 layers of equal size, each by the power of 2. 
 
-.  After you open the image you select Filters/Generic/Cubemap Layer Generator.
-.  Fill in the details. 
-**  Source 
-**  power of 2 (10 for 1024 sized Layers) 
-**  Cubemap layout (Cross Horizontal)
-.  Slice up the image.
-.  Change file type and name to .dds and choose your location to export into.
-.  Click export.
-* In the dds exporter select none for compression
-* Select RGB8 for the format
-* Select Save: as cube map
-* Select No mipmaps
-. Export
+.  After you open the image you select menu:Filters[Generic > Cubemap Layers Generator].
+.  Fill in the details as follows. 
+**  Source: navigate to the image you are slicing.
+**  Cubemap layout (Cross Horizontal)
+**  2 to the power of: (10 for 1024 sized Layers) 
+.  Press btn:[OK] to slice up the image.
+.  Select menu:File[Export As] and change name to and file type to .dds and choose your save location to export into.
+.  Press btn:[Export].
+* In the dds exporter select none for compression.
+* Select RGB8 for the format.
+* Select Save: as cube map.
+* Select No mipmaps.
+. Press btn:[OK] to export.
 
 You add it to your scene as is explained in the <<jme3/advanced/sky#,How to add a Sky to your Scene>> tutorial.