For offline you just choose the skin as required. For online when you join the SRO server, because I have assigned the Jordan skin to you in the server configuration, you will get it automatically.
Any specific race rules regarding pit stops etc. would be listed in the series forum, in the race forum page and on the race page itself under Event Details.
That's set in the server. You'll get the correct skin in the race tonight (Providing Ken hasn't made a mistake), and will probably get it in all future practice sessions also. You haven't got it for this practice server because Ken would have to constantly edit and restart every-time someone picks a skin. *edit* weirdly the posts above mine only appeared after I posted.....
Paul can you please run a lap on our server so I can get your STEAM ID or alternatively PM me it directly. I need it to assign the skin to you.