Designate several drivers to take groups of guests on the road rally. Be sure to let the driver know the true destination just in case clues get botched.

Before the party, map out a course to the party's secret location.

On the day of the party, leave clues in appropriate places along the road to the party.

Provide each set of guests with a treasure map on the day of the party. Ideally, each group should have a separate set of clues which converge on the party. The map leads them to the first clue.