Tutorial written by Abduzeedo
Step 1: Open Photoshop and create a new document. I am using 2560x1440 pixels. After that fill the background layer with grey using the Paint Bucket Tool (G)
Step 2: Go to Filter>Texture>Craquelure. Use 9 for the Crack Spacing, 2 for Crack Depth and 10 for Crack Brightness.
Step 3: Go to Layer>Layer Styles>Color Overlay. Use black for the color and Multiply at 70% Opacity.
Step 4: Go to Image>Adjustments>Levels. Use 120 for the black input, 1.00 for the grey and 181 for the white input.
Step 5: With the Ellipse Tool (U) create a circle in the center of your design.
Step 6: Select the Gradient Tool (G) then click on the color preset. Change the colors so you have something like the image below.
Step 7: Add a new layer and the with the Gradient Tool (G) select the Angle Gradient type and fill the layer with the gradient preset we created in the previous step. After that create a marquee selection of the circle we created in the step 5, to do that is super simple, just click holding Command (mac)/Control (PC) on the thumb of the circle layer.
Step 8: Go to Layer>Layer Mask>Reveal Selection.
Step 9: Duplicate the circle layer and fill it with white. Change the order so it is on top of the other layers. After that change the Fill Opacity to 0%.
Step 11: Go to Layer>Layer Styles>Inner Shadow. Use Color Dodge for the Blend Mode, white for the Color, 90 for the Angle and 70% for Opacity. After that use 8 pixels for the Distance, 11% for the Choke and 7 pixels for the Size. For the Quality change the Contour for the one we used in the image below.
Step 12: Select Inner Glow. For the Blend Mode use Overlay, for the Opacity 36% and for the Color use White. Also change the Source to Center, Choke to 12% and 65 pixels for the Size. Also change the Contour to the one I used below.
Step 13: Select Bevel and Emboss. Use Emboss for the Style, Smooth for the Technique, 1000% for the Depth, Up for the Direction, 50 pixels for the Size, 0 pixels for the Soften. For the Shading, change the Angle to 90º at 30 º Altitude. Also change the Gloss Contour to the one I am using below. For the Highlight Mode change the Opacity to 0 while for the Shadow Mode use black with Multiply at 100%.
Step 14: Duplicate the circle layer and move to the top, make sure it is white. After that go to Filter>Pixelate>Mezzotint. Use Fine Dots.
Step 15: Create a marquee selection of the circle and then go to Filter>Blur>Radial Blur. Use 20 for the Amount, Spin for the Blur Method and Best for the Quality.
Step 16: Change the Blend Mode to Multiply.
Step 17: Select all layers used to create the button/tuner, then go to Layer>Group Layers. After that duplicate the group and resize it like the image below.
Step 18: Select the layer with the layer styles inside the group and then change the Color Overlay to Black with black for the Blend Mode at 45%.
Step 19: Add drop shadow to both circles the bigger and the smaller. Like the first circle in the stack of layers that were used to create the effect.
Step 20: With the Rectangle Tool (U) create a square holding Shift. After that rotate the square 45º and position it like the image below.
Step 21: Go to Layer>Layer Style>Drop Shadow. Use Normal for the Blend Mode and Black for the Color at 100%. For the Angle use 120º, 5 pixels for the Distance and 5 pixels for the Size.
Step 22: Select Inner Glow. For the Blend Mode use Color Dodge, for the Opacity use 70%. Change the Choke to 10% and the SIze to 9 pixels. For the Quality use the preset I used in the image below.
Step 23: Select Gradient Overlay. Use dark red and light red for the gradient colors like the image below. Also change the Style to Linear and the Angle to 180º.
Step 24: This is the effect you will get after all the layer styles. It's pretty good but it is still to uniform and with the computer look.
Step 25: To change that lets use a metal texture. The one I am using is courtesy of Shutterstock and you can find it at: http://www.shutterstock.com/pic-20761540/stock-photo-metal-plate-background-texture.html
Step 26: Change the Blend Mode of the metal texture to Overlay at 30% and mask it using the big circle as reference, this way the texture will be on top of the other layers. Done!