OH.
Well, they are already marked at 64x64 pixels and all you should have to do is follow the instructions at the front of this thread.
Avatar Help: Need a picture next to your membername?
Due to the many new members and the frequent requests we get for avatar help, this discussion has been created and will be at the top of our "Website and Forum" folder. This thread is where you can request help with all aspects of your avatar.
You can add an avatar by clicking on the “user control panel” link above. Then, choose “edit options” and you can then upload an image from your hard drive to use with your account. Since linking images from free Web sites is increasingly difficult, we will host one image per member for free. The image should be a maximum of 64 by 64 pixels. If your image is too large or if you need help finding an image, please politely post in this discussion that you are needing avatar help. It's important that you not take an avatar of another forum member. Each picture is representative of a unique person.