Sign in to your Gmail account.
In the upper right hand corner click on the image of a gear. Select The “Mail Settings” option from the drop-down box.
A page display the General Settings options. select the Signature from the almost middle of this page.
You can simply write the signature which you want to display in each of your sending mail.
If you want to add the your picture then click on photo icon which is circle in above image.
Now in this appearing box Gmail ask for Internet address of your image. (Its may be a problem for those who have no such URL).
(Simple solution is open a n Google drive account and save a picture on it then open this picture copy the address)
After entering the URl of your picture its take a few minute depending on you picture size and the your picture appear in box below.
Click on Ok button
and in the end click on Save Change button in the bottom of this Setting Page.
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