This free Photoshop + HTML template is gonna help you to generate and test automatically your favicons in every needed resolution.It’s been created by Chrometaphore ( Lorenzo)
Actually there are so many different sizes that should be provided to offer the best possible experience on different browsers and devices.
Once you save your edited favicons.psd document, you are mostly good to go.
If you have File > Generate > Image assets checked, all assets will be generated
directly into favicons-assets/ folder.
You can manually export your favicons usign File > Save for Web. Since this method
uses slices, you are gonna have to do a little of spring cleaning into the generated
assets/ folder.
If you want to use the html template included in the .zip package,you might
want to move your manually generated assets into favicons-assets/ folder.
For compatibility with IE6-7-8-9-10 (doh!), you need to generate a .ico file out of the 16×16 png icon. To generate ico files with Photoshop, this free plugin does the trick: http://www.telegraphics.com.au/svn/icoformat/trunk/dist/README.html