How

On the top of the website you will see your name next to conversations and alerts. If you hover over your name a drop down menu should appear, and you will find something called 'Signature' below that. Once you click that, you will come to a page like this:



You can type anything in the white box if you want text. Now if you want a picture, then all you do is click the mountain icon located next to the smile face, and insert a link to a picture. Click 'Insert', then a picture will be inserted, and then click 'Save Changes'.

 

If you navigate to your signature,

you should be able to click the little image button

and insert an imgur link. The image you select will show under every post you make.

You know how long it took me to make this reply, Audi? omggg