So that it's in .jpg format, and also it'd be appreciated to link me to something that can make it the appropriate size (40X40?)

First, just resize the image in Microsoft Paint or Preview (for mac people). Second, click "save as" and select ".jpg" from the drop-down menu under the name input box.
Quote by dr_shred
FrustratedRocka you are a legend

Quote by littlephil

The man clearly knows his shit.

Quote by Banjocal

one of the best, educated and logical posts I've ever seen on UG in the Pit. Well done good sir.

Just take a images of your screen or a screenshot of your online play and upload the photo to our wall.
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