Huh? You mean how to put a picture on your sig??? If that's your question, I bet you already know. ^ ^ Well, just in case...

-On the page of Edit Profile (Psh, I think)
-Look for the box with SIG next to it or something
-Do you have the picture URL copied yet???
-See all of those little buttons on top of the box?
-Try to spot a button that says MANAGER. I've never clicked on that button but...
-Click on the button on the left of it
-A window-ish thingy should open
-THAT'S when you enter your image URL
-Press enter or whatever you do to proceed. X3
-I usually press enter again because I dunno what the next step does. XD
-Then, you should test it out to see if it works

And if THAT'S not what you were asking for, HOLY CRAP! You made me write so MUCH!!! O_o