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How do I create an Avatar, to display on my User Page and next to my Comments?
Firstly you will want to make sure that the avatar you're going to create is 50px x 50px in width and height and saved in one of the following formats (GIF, JPEG or PNG) only, in the end or it will not work when you try and upload it.
1.) You can create an image from scratch, following the specifications for an avatar, in the Graphics Program of your choice.
2.) If you wish to use an image and resize it to the specifications for an avatar, you can do so using an image editor of your choice.