I know so many tuts about how to change blogger
favicon, unfortunately, most of them have not clear explanation. Because,
inserting your link code between tag head not enough, they missed one condition,
you must insert your code between tag head and below the blogger standard head tag. This is all you need to do.
Create / Upload Your Icon
You need to create and upload you image file on a photo hosting file such as
imagebeep or just upload it on your blog (only .png and .gif file)
Link Code
<link href="{image url}" rel="shortcut icon" />
replace
{image url} with your exact image