Create a new file that would have 1024x768 px and 72 dpi and select the Rectangle Tool (U) to represent the background of the next picture to be.
Blending Options-Gradient Overlay
Gradient's parameters:
Choose the Ellipse Tool (U) to draw a kind of illumination around the circle:
Fill 0% on the layers.
Blending Options-Outer Glow
Select the same tool just to draw one more layer reserved for the sphere.
Blending Options-Outer Glow
Blending Options-Inner Glow
Blending Options-Gradient Overlay
Gradient's parameters:
Choose the same Ellipse Tool (U) to represent that necessary layer that would give volume to the sphere.
Click on the Add a Mask on the layers and apply the Eraser Tool (E) to erase the unnecessary elements the way it is shown on the next picture.
Fill 0% on the layers.
Blending Options-Gradient Overlay
Gradient's parameters:
Chose now the Pen Tool (P) to create the first element of the ornament:
Blending Options-Outer Glow
Blending Options-Color Overlay
Apply the same previous method to draw three more elements of the ornament to be.
For your convenience we have to combine in a group all the layers composing the ornament. The Opacity on the group's layers should be of 70%.
Make a copy of the new made group and choose the Free Transform option to turn it over and place it the way it is demonstrated next picture.
Using the Ellipse Tool (U) we need to draw several more circles giving volume to our sphere.
Fill 0% on the layers.
Blending Options-Gradient Overlay
Gradient's parameters:
Make a copy of that new layer represented earlier and apply again the Free Transform selection to make it smaller and place it the same way it is indicated next image.
More Tutorials: 
