Google Product Forums
Re: How do I create a signature for when I leave a comment on someone else's blog???
It depends on the blog.
But if you're trying to do that ion order to plant links to yrou site, be aware that:
1) Google will consider this an unnatural link to your site
2) The blog owner will consider this spamming
3) Most blogs/forums are set up to add rel="nofollow" to all links that appear in guest posts and comments, precisely in order to discourage spamming