Everything in it's time. Don't try to answer all possible questions in the least possible time. Stretch out the process to cover the first weeks or even months on the job. This lets new staff absorb essential information more gradually and completely. An extended orientation program also reassures new employees.
Newcomers are always under great pressure to perform and adapt.
Your extended program shows you understand their situation, you care about their adjustment, and you will continue to show interest and attention over time. Involve everyone in the process. New employees are not the only ones affected by the quality of your orientation program. Other groups are influenced during this important period as well, including peers, bosses, subordinates, senior managers, customers, suppliers and even the new hire's family back home. Each group has different questions and concerns about the new employee.