When sizing graphics, try to work with originals, before any compression, and with the highest color count possible.
Always crop first, then resize the image. To make a small square out of a rectangle, crop the square first then resize smaller.
Always keep your aspect ratio correct to prevent graphics from becoming skewed when re-sized. If you resize a rectangle to a square the image will be skewed and distorted.
On web pages, don't use the width or height attributes in the image (img) tag to resize graphics. Best results are always obtained when they are used for the purpose of providing the actual pixel size of the image to the browser.
