1. Create your own favicon. You can use favicon generator tool here.
2. Upload your favicon to free web hosting like Geocities.
3. Open your blogger then open Layout -> Edit html
4. Add this code BEFORE HEAD TAG. (Some site say to add this code after HEAD tag, but in some cases, IT WONT WORK).
link href="http://YOUR_URL_PATH/favicon.ico" rel="'shortcut"
5.Save your Template.
Good luck...if there are something you wanna ask, just send me comment. Thanks.
*please add symbol less than "<" or bigger than">" in front of and at the and of the code. (because i didn't understand how to add code this post.T_T)