Gmail allows you to create a default signature which will be added to each message you compose. You can format the signature text and add images e.g. company logos. You can create additional signatures to add to messages as required.
When you create a new message in Gmail, your default signature will be added.
To change this:
Click on the Signature button along the bottom of the message
Choose a different signature to add it to the message
Choose No signature to remove the signature
Choose Manage signatures to add new signatures or edit existing signatures
To create a new signature:
Click on Create New
Type a name for your new signature
Enter your signature text in the large box
Format text by dragging the mouse over the text to select it, then use the buttons on the toolbar to change the format of the selected text (see table below)
Add an image by clicking on the Insert Image button.
You can add an image from a folder on Google Drive, or click on the Upload link to upload an image stored on a local drive on your computer. In addition, you can click on the Web Address (URL) link to add an image by entering the URL at which the image can be found on the web.
To add a link e.g. to your website, type the text to show in your signature, then select it and click on the Link button. Enter the URL for the link, then click on OK
Choose the signature to use by default for new messages you create, and messages you create in reply to received messages
Scroll down the screen and click on the Save Changes button
Use the toolbar along the bottom of the signature to format your text e.g. by adding bold, italics, colour or setting the alignment of text.
Choose the signature you wish to use by default for new emails
Choose the signature you wish to use by default when replying to an email
In Gmail, when you reply to an email, the original message is quoted below your response, typically with a line (--) separating them. You can use the checkbox under Signature Defaults to show your signature directly below your response and remove the sepation line, showing your signature more prominently with a cleaner look.
To edit signatures without creating a message first:
Click on the Settings cog in the top-right corner of the screen
Choose See all Settings
Scroll down to the Signature options