Used this shape
Isometric Shapes II (13)
http://thesuper.deviantart.com/art/Isometric-Shapes-II-69632010
Cut every part from the shape and make it in new layer and give every part layer style (just 2)
Drop shadow
Blend mode multiply
Color 00000
Opacity 75%
Angle 90
Distance 12
Spread 2
Size 8
And give every layer linear gradient (spectrum)

sources used for this step: