How to use CDJ NXS2 with Rekordbox DJ HID?

Hi

This may be a very simple and stupid question, but is there any easy step by step quick start tutorial on how to use Rekordbox DJ with CDJ-2000 NXS2 using HID?

I usually play with Traktor (Macbook with Yosemite) and CDJs in HID mode. Over there, I connect both CDJs with an USB cable, aggregate the two CDJs into one device in the Audio-Midi-Settings, select it in Traktor, choose "Link" and corresponding Traktor Deck on the CDJs and start playing.

How is this done in Rekordbox DJ? More and more promoters/clubs rent/buy NXS2 and I'd really like to start using Rekordbox DJ in general instead of Traktor. Therefore I even bought Rekordbox DJ, but when at the gig (I don't have CDJs at home), I always end up using my Rekordbox-prepared USB-Stick instead.

Any help?

Thanks

Darrien