First, make sure that you own the copyright to the image that you are going to upload. Pictures that you take make perfect avatars. Images must be in either the jpg or png file format and be larger than 140x140 px. Square images work best on Postcrossing. Ready?

1. Verify that you are logged in to Postcrossing.com.
2. Select Edit > Avatar from menu.
3. Select Browse... and choose your avatar image from your computer.
4. Select the Upload file button. Wait. It may take a few minutes for your image to upload.
5. Crop your image. You can change the size of the crop area by dragging any one of the eight handles (small squares on the corners and sides). A preview of what your image will look like cropped appears to the right.
6. Once you are happy with the preview, select the Crop button.

Your new avatar is now uploaded. You can change your current avatar using these same steps.