Diageo: Assessment Centre- Tips & Wrinkles?

Hi,

Just found out that I passed the telephone interview and now have an upcoming assessment centre for the HR Graduate Scheme with Diageo. I'm currently working for another big company in HR but this is my first assessment centre so I'm quite nervous already! Day includes: Group Exercise, Comptency- Based Interview with two managers, Individual Presentation and Role-Play.

Just wondered if anybody who had been to a Diageo assessment centre/ any others for HR had any advice? I will obviously be keeping up to date with news within the industry, preparing examples for the interview & brushing up on specific HR knowledge e.t.c. I'm more curious about the group exercise and role play? Reading all the info here on wikijob it seems to be fairly tricky to get the balance right between being vocal and confident whilst also being a team player... Also I've got no idea as to what a role play will actually entail....

Lastly the presentation material is the same for all the participants so just wondering if anyone has any tips on how to make yours stand out for the right reasons?! Thinking all the standard things like, keep it simple, structure my argument, be confident, stay calm, lots of eye contact e.t.c. e.t.c.

Any tips and wrinkles would be so very much appreciated, I'm dying for this job!

Thanks guys