oh and one thing more. Don´t look at what the other ones do. keep the eyes and concentration on your own work.
I once got so nervous, and started to look around, and everybody around me was building big skulptures out of nothing.
An the assignment was a normal bouquet.
So I started building my bouquet bigger and bigger. Three had totally misunderstood the asignment, the ones around me.

and my bouquet had lost all it´s form. So it to was put down.
Had I only stuck to the first plan in my head. expensive learning.