I am using photoshop CS3 but this will also work with any version of photoshop.. Final Project attached below.
This tutorial is intended for any level of users. Hopefully we'll end up with an ORB similar to what I've use here..

Steps:
I. Create a new 200 x 200 project with black or anything dark background.
II. Create a new Layer and Draw a circle in it.


note:
1. You can use the SHAPE tool to create a CIRCLE.
2. You can use the Elliptical Marquee tool and CTRL+BACKSPACE to fill it.
3. To create a Perfect circle you can HOLD SHIFT while drawing it.
III. Using the Layer Style
1. Simply double click layer 2 to open its Layer Style.
2. In the Layer Style Click the Gradient Overlay to open its property.
3. Set the property settings to match with the settings below.

4. Click the gradient below to open the gradient editor. ( Read outlined )

IV. Using the Gradient Editor

1. The darkest Color in the gradient.
2. The lightest Color in the gradient.
3. Click #1 to enable #2 ..

4. Click #2 to open the Color Dialog. Since were setting the dark part of the gradient, you should select a dark color.. lmao.. See below..

note:
a: #1 is the color pointer
b: #2 is self explanatory.. click it when your done..
5. Follow the same procedure in setting the lightest color for our gradient.
You should hopefully have something similar from mine.

V. Adding the COOLEST EFFECT : This is essential in creating anything shiny.

1. Make sure the Rectangular Marquee tool is selected.
2. Add a new blank layer.
3. While the new layer is selected, hold control key(CTRL) and click on the icon of layer 2 (Layer 2 is were your circle reside).
4. You should have by now a circular selection like the above image.
5. Use your arrow keys (keyboard) to move the selection.. See below..

6. I need your FOCUS right now.. this method is one of the most Important and well used method In my whole photoshop life..
7. While the new empty layer is STILL SELECTED.. HOLD CTRL+SHIFT+ALT then click on the ICON of layer 2 (layer 2 is were your circle reside).
8. You should have a selection same as below.

9. Set your foreground color to white.. see above..
10. Hold ALT then press BackSpace to fill the new empty layer with white color..

11. Set the blending mode to SOFT LIGHT.. and play with the opacity to get the desired effect.. AT LAST ITS DONE..
VI. Last notes
1. You just learned the two most Important and well used shortcut keys for me..
a. CTRL+CLICK the Layer ICON to select the image in that layer.
b. CTRL+SHIFT+ALT to Adjust the selection to match the image Selected.
2. The final Image shown above is done using those techniques.. and those methods could be used in any graphic designing that concerns shiny effects. like ICONS, GLASSY ORBS, USERBARS, etc..






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