I highly recommend you either don't do it or get proper formation training first, there is nothing anyone here can tell you that would make you formation proficient. On a different note, in my opinion spread formation is more dangerous than close formation, especially when you're not trained. In close formation you're only looking at the flight lead, in spread formation you're doing plenty of other tasks such a scanning for other traffic. What often happens when you're scanning for other traffic or navigating is you lose your flight lead and end up colliding into him. So if I were you I'd either get proper training or depart 30min apart.
