There are Two different ways you can Upload an Image to your Email Signature using the HTML.

First, use an Image already Saved on your Computer.

Second, you can add an Image using a Direct Link.
If you choose this method.
You have to Upload the Image to an Image Hosting website.
Enter Image Hosting in any Search Engine.
Copy the Direct Link for the Image.
IMPORTANT:
Make sure the Direct Link ends in an Image Extension. (example: imagehostingsite.com/#####.jpg)

The First method is the easiest.

Once you Choose a method.
Click on Your Name in the top right corner.
A menu will open.
Click on the first item that says Account Settings.
In the Profile menu.
Click on the Signatures item.

In the Body of the Email Signature Option 1: HTML.
Click on the Image button.
A window will open.

If you Choose the First method.
Click on the CHOOSE FILE button.
A window will open.
Select the Image you want to use.
Click the INSERT IMAGE button near the bottom right corner of the window.

If you Choose the Second method.
Paste the Direct Link to your Image in the bar.
Click the INSERT IMAGE button near the bottom right corner of the window.

After the Image is Inserted.
Click the SAVE button near the bottom right corner of the Email Signature Option 1: HTML section.

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