Square Cropping a face using basic MS Paint or Photoshop
Many profile pictures have a default size of square. If you upload a rectangle, it'll display your picture cut off! Best solution is to crop your picture to make a perfect square out of it so the entire image is shown.
Its really not rocket science. Here's my quick way that I crop a picture so I get a perfect square. I use the basic Microsoft Paint (which is installed in EVERY PC on default) or Adobe Photoshop.
I hope this helps! :)