• Resize your images manually, or have your CMS or image proxy do the cropping.
• The Visual Framework CSS will try to handle incorrectly sized or wrong aspect ratio image as a 'fallback'.
• Consider adding width and height to help the layout engine in browsers.
• Be sure to use appropriate alt text for accessibility.
  • Also consult the accessibility guidelines
• Use the correct image compression format (JPEG for photographs, PNG for vector or logo-style reduced colour count images).
  • If you have artwork, you may want to use and SVG instead.
• Optimise for file size.
• If your image has a caption, you probably want to use the vf-figure.