Here is a very quick and very easy little tutorial to help photoshop beginners create a semi-realistic, simple button and/or light.
Step 1. Create a new document 500px by 500px with a background color of black.
2. Using the ellipse tool and holding shift draw a 300px by 300px circle with a gray color. I used #adadad. Name this layer “outer ring”
3. Next, go to the top menu and click on Layer -> Layer Style -> Bevel and Emboss. In the pop-up change the settings to reflect the following screen shot.
4. Copy the “outer ring” layer and rename the new layer “inner ring”. Re-size the circle on the “inner ring” layer to 80% or 240px by 240px. Go to the top menu and click on Layer -> Layer Style -> Bevel and Emboss and change the settings to match the the following screen shot.
5. Copy the “inner ring” layer and rename the new layer “light”. Re-size the circle on the “light” layer to 90% or 216px by 216px. Once again change the Bevel and Emboss settings by going to the top menu and clicking on Layer -> Layer Style -> Bevel and Emboss. Make sure your settings match the settings in the following screen shot.
You image should now look something like this…
6. Finally, double click on the layer thumbnail in the layers pallet for the layer named “light” and change the color to #ff0000. Now you have a semi-realistic red light/button. Play around with the settings and colors to create various different versions.