If xfire is on simply press the scroll lock key and S (scroll lock+S)
this will take pictures.Then when you go to desktop after game it will ask you if you want to upload..you click yes.Then go to image shack, click browse, go to recent documents, screenshots,
right click screen shot and preview to make sure its what you want, then left click it, click host image, then a list will appear with like 5 diff links, choose the one all the way on the bottom, left click it then right click and copy, then go to our forums and post, then right click and paste to drop a link or if you want them to see the actual picture type BBC codes before and after paste...like this

also when you want to change youre signature you do the same thing but you do the bbc code and paste in youre signature options.
Hope this helps

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"Serviendo Guberno""We do not rise to the level of our expectations. We fall to the level of our training"