How to access H1 tag in Wordpress?

I have installed Wordpress in my site. Created my home page and posted. The problem is When I saw the site, it is showing mysite.com as H1 tag. I don't know when I set it. I want change it to my keyword. The problem is I searched all the settings but unable to find a way to change my H1 tag. I can't access it from anywhere. Can anybody tell me where is the settings for H1 tag in wordpress? Thanks in advance. (Hostgator + Wordpress + Weaver Theme).

Got it. Sorry to bother you guys.

Im interessed in this too
thanks

It's in the menu. You first have to expand the menu by pressing on a small weird icon (two rectangular, like a keyboard) and then you can change the format to H1 in the dropdown.

Sorry for my english.