The final paragraph should end positively and courteously stating any expected outcome or actions. The actual content will depending on the audience and purpose of the memo. For example, the final...

The final paragraph should end positively and courteously stating any expected outcome or actions. The actual content will depending on the audience and purpose of the memo. For example, the final statement could:
o     Explain that no further action is necessary on the part of the recipient, but offer to discuss the content of the memo further and explain that you will keep the recipient updated on progress.
o    Ask for  comments by a particular date (e.g. “Please send me your comments and suggestions by February 25th)
o    Suggest a meeting to discuss  the details and future plans further (e.g. “I would be happy to meet early next week to discuss any details and future plans regarding the next stage in the project” )
A signature is not always required at the end of a memo. However, you can end the memo with a salutation such as “kind regards” or “thank you” followed by your name. You can choose to use either your first name or your first and last name depending on how well you know the recipient and the formality  of the memo.