Step One
Create a new image, lets say 100 x 100 pixels, with a white background, then fill the canvas with the color of your choice, I'm going to be boring and choose a shade of grey - #DADADA It should now look like the image to the left.
Step Two
Now turn on the rulers ( view--rulers ) and drag some guides out into the center of your canvas (click on the ruler and drag the guide out) and it will look like this.
Step Three
Create a new layer, and on that layer, drag out a circle from the center of the canvas, by holding shift + alt then dragging out from the center, next fill the circle with white. (make white the foreground color and press alt + backspace) It should now look like this.
Step Four
Now with the new layer selected, go layers--layer styles--outer glow and enter the settings shown to the left.
Step Five
This should generate the image shown to the left.
Step Six
Next, onto the inner glow panel and use the settings shown to the left...
Step Seven
...To generate the image shown to the left.
Step Eight
Next, onto the bevel and emboss panel and use these settings.
Step Nine
You should have something like this now.
Step Ten
Next use a gradient overlay with these settings...
Step Eleven
...then satin with these settings...
Step Twelve
... and you should have a nice blue orb like that shwon to the left!
Step Thirteen
Now, to make it inset, we create a new layer under the orb layer, and drag a circle slightly larger than the orb, and drag a gradient from top to bottom, as shown. Now, all that remains to be done is to blur the inset bit, do this using a gaussian blur, (filter--blur--gaussian blur) and enter a setting of around about 1.5.
Here is my final result, note that the images used in the tutorial are a slightly bigger size for clarity.
And of course, experiment!
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