flat design - Photoshop : how to create a menu button subtly pushed

I found the following question : Photoshop: how to create buttons that look "subtly pushed"? and I fell in love with the menu (Dashboard, contacts, deals, mail).

I tried to reproduce it but I can't. I'm a photoshop noob. I made a rectangle with gradient overlay, picked the colors from the picture itself. Then I made shape, tried inner shadows and white dropped shadow. Still, not as good as the original. The green ribbon has 1 pixel lines on the top and the bottom. I d'ont understand how their color has been chosen (or maybe it's just playing with layers and opacity). For the CONTACTS button that looks pushed, I tried inner shadow and also noise and a subtle light that seems to come from the bottom, still, not as good as the original.

I exactly need that kind of menu for a personnal app. Can anyone tell how to make it ?

Here is what I made so far (I 'duplicated' the DASHBOARD icon with the pen tool).