Step:1
Create a new image, File > New set the Width to 800 and the Height to 600. Set the background color to white #FFFFFF
Step: 2
Click on the Elliptical Marquee Tool
, and add the setting below.
Create a circle on your work area and fill
it with this color #aa3030. Now right click on the layer with the circle and click Blending Options and add the setting below.
If you did everything right you should have something like I have below.
Step 3:
To change the color of your LED right click on your layer and click Blending Options add the setting below.
That's it. Here is my finish example.
More Tutorials: 
