click the [ Polygonal lasso tool (L) ]
Make a selection as shown.

Press Ctrl + N to create a new layer.

fill it to color #000000.

Making style
Double click the layer or go to Layers->Blending options and apply settings as shown.

Here is the result:

Select the [ Pencil Tool (B) ]

Press Ctrl + N to create a new layer.

Make a line as shown.

Congratulation!, you finished it!

Now just add your titles to navigation bar.

heres is the final result.

Rollover Version