Right-click the picture you want to make a signature file, and a menu will appear. There is "Properties" in the bottom line of the menu. Click on it, and a box will appear. There is an "Address" in the box. This is the image. Copy the link address (note that the address of some pictures must be copied is very long). Paste it into the picture link in the signature file. Enter the name and click Upload to use it (but please note that the links to some pictures are invalid. The specific solution is to right-click on you. Click on the picture you want to use as a signature file and save it on your computer

Then enter the i bar (that’s your feed) or enter any post bar and save your picture on your computer and upload it once

(You should know that there is a way to add content under the i bar, click and then click to insert pictures to upload pictures locally. You can upload pictures from your computer.) The uploaded picture address can be used as a signature file)