It's important to point out there is a difference between an avatar, and a profile picture. An avatar is the picture that shows up on all of your posts. A profile picture is the picture that is on your personal profile page.

*The maximum file size for an avatar is 100x100 pixels or 29.3kb (Whichever is smaller). Make sure your picture meets these requirements or your picture will not upload.*

So the first step is to scroll to the top of the page, in the upper right hand corner there is a panel, click on settings. (see pic #1).
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A new page will load. On the new page you want to look on the left, under the "My Settings" section click on "edit avatar" (Circled in red in the pic below).

If your looking to edit your profile picture simply click on the "edit profile picture" (Circled in blue in the pic below).
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From here a new page will load, whether you are editing your avatar or profile picture the last step is the same. (For my example I chose the edit avatar page).

There are two options; you can either upload your avatar from a URL (Which is circled in red), or upload from your computer (Circled in blue). With the URL option all you have to do is enter the direct link into the box. With the Computer option, you have to click browse, find the file you want, and then upload it.

Then the last thing is to click save changes (Circled in green).
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