Here's how you use it.

{{Olympics infobox |
  Name                   = Games of the XXVII Olympiad |
  Logo                   = 2000summerolympicslogo.jpg |
  Size                   = 250 |
  Optional caption       =  |
  Host city              = [[Sydney]], [[Australia]] |
  Nations participating  = 199 |
  Athletes participating = 10,651<br>(6,582 men, 4,069 women)|
  Events                 = 300 in 28 [[sport]]s |
  Opening ceremony       = [[September 15]], [[2000]] |
  Closing ceremony       = [[October 1]], [[2000]] |
  Officially opened by   = [[William Deane]] |
  Athlete's Oath         = [[Rechelle Hawkes]] |
  Judge's Oath           = [[Peter Kerr]] |
  Olympic Torch          = [[Cathy Freeman]] |
  Stadium                = [[Telstra Stadium|Stadium Australia]] |
}}

or the empty box version:

{{Olympics infobox |
  Name                   =  |
  Logo                   =  |
  Size                   =  |
  Optional caption       =  |
  Host city              =  |
  Nations participating  =  |
  Athletes participating =  |
  Events                 =  |
  Opening ceremony       =  |
  Closing ceremony       =  |
  Officially opened by   =  |
  Athlete's Oath         =  |
  Judge's Oath           =  |
  Olympic Torch          =  |
  Stadium                =  |
}}

Here's what it looks like: