Step seven:

Create a new layer-set, were going to the first button in this layer-set so it's easier to make the rest.

In a new layer, draw a smaller #FFFFFF circle on the left side of the case.

Add the following layer-styles: Inner Glow, Bevel and Emboss, Stroke.

Add a letter or number to represent the button, In this tutorial i'm using font Verdana.

Step seven:

Now make the rest of the buttons by duplicating the first button's layer-styles.