Step nine:

Create a new layer-set called Side details.

In a new layer, create a thick black line similar to the picture guide.

Add the following layer styles: Gradient Overlay, Stroke.

Duplicate the line four more times and position it next to each other. Merge the original and the duplicate layer so you end up with one layer.

Step ten:

Rotate the metallic piece you made in step nine. Position it on the bottom left of the case.

Add an Inner Shadow layer styles.