You don't. I imposed a restriction because a lot of people were taking the piss by having half a dozen trainer card images one after another in their signatures - not to mention other pictures.
IF people can be expected to be sensible, I will remove the restriction again, but frankly, considering the shit that's gone on in this place for the last month/two months, I doubt there's more than a handful of people on here that can be trusted to not be a fucking moron any more.
If that's true, why does Uzumaki_Naruto have 2 images in their signature?