Ideas for making sure all the bases are covered prior to termination?

You Can:
Invite the employee to take a seat
Explain why they are being terminated
Be direct and to the point
Clear and consistent, re-iterate if possible.
Outline separation package- if necessary
Keep meeting short as possible- max 15-20 minutes
You Can't:
Engaging in non-business related discussions
Trying to incorporate humor into the situation
Giving off the impression of sympathy
Mentioning other employees
Trying to minimize the importance of the situation
Using phrases like "I know how you feel" or "I know you'll find another job."
Making the decision a personal matter.