how can i clam my blogs?

it means that you will show them that that you have the right permission to post on the blog you have mentioned to be yours. Well this is to avoid fraudulant claims of blogs as theirs. What you are supposed to do is that, whatever javascript is provided to you by the rss aggregator, you must paste it on your site where a javascript will function properly. Then you have to tell them that you have pasted and saved the content that they have provided and that they can check back. The site in question will check if the javascript with the code provided by them to you has been posted or not. If it has been posted, you just prove that the blog belongs to you and that your claim accepted.