If you prefer to add your signature on a message-by-message basis — that is, if you don't want a signature added automatically to new messages — you can adjust your settings in Outlook. In the Signatures and Stationery dialog box, click (none) in the New messages list under Choose default signature.
Then, when you want to add a signature to your message, use the Signature button on the Ribbon, in the Include group.
Note that once it's in a message, you can delete a signature at any time by selecting it and pressing the DELETE key.
