Adding signatures to Gmail accounts

    Not everyone uses signatures for their daily email, but many people find it invaluable. You can use anything from a simple name or favorite saying all the way up to including contact info and work position. Or, you can do anything in between.

          Creating a signature in the native Gmail app in Android is dead easy, just launch Gmail and go to Menu > More > Settings > Signature. So far, you can only have one signature per account, but you can create different signatures for each Gmail account you have. Perhaps this is a feature Google will include in a future update (which should be much easier now that Gmail is a stand-alone app), but we will all have to live with just one signature for now.

source: http://www.androidcentral.com/adding-signatures-gmail-accounts

Adding signatures to Gmail accounts