Basically when you click on label or category widget, the link will lead you to search page. Because it lead to result search page, this type of link is not a good SEO practice. Google as a big search engine company will recommend its bot to not index all these link. Label widget function is just to help visitor, not to take over search engine function. Often I see blog owner added so many label on their post.
If you don’t apply NoFollow tag, google will see your blog as a spammy blog and it also can caused duplicate content. Now, how to add this tag on your blog?, follow the tutorial below:
1. Go to Template area and click Edit HTML button.
2. Find this part:
<a expr:dir=’data:blog.languageDirection’ expr:href=’data:label.url’><data:label.name/></a>
and put rel=”nofollow”, so it will look like this:
<a expr:dir=’data:blog.languageDirection’ expr:href=’data:label.url’ rel=”nofollow”><data:label.name/></a>
There are 2 section that have this code on your template, so you need to add the tag to both of them. This tag only apply for label widget not for post-footer or breadcrumbs. For a better result you can customize your robots.txt and robot header tags.
Hope this helpful!.