Microsoft Outlook provides options to set email signatures for your email messages. You can set different signatures for a new messages and another one for all replies or forward messages. Listed below are steps for adding signatures to email messages in Outlook 2013, 2010 and 2007
Add signature in Outlook 2013 and Outlook 2010
Click File menu and select Options from the menu list.
In the Outlook Options window, click Signatures under Mail tab.
Signatures and Stationery window provides users with option to create New signature. And using Choose default signature section, you can set the signature for New messages and Replies/forwards for the configured email accounts.
Add signature in Outlook 2007
Tools -> Options -> Mail Format tab
click on the Signatures button, which should display the following Signatures and Stationery dialog
You need to create two signatures, one for New messages and another for Replies/Forwards, this can be done by clicking New button. For example, I have created two signatures, Ravi Replies and Ravi New Messages. After creating these signatures, click on the drop down adjacent to New Messages and Replies/Forward and select the appropriate signatures. And click OK to save this changes.