When you visit your website for the first time, it will look something like this:
I know – a little bland, huh? You’ll fix that later. On this default website, you’ll see a section in the lower-right like this:
Just click on the “Log in” link. Also, in the future, you may choose a website theme that doesn’t show these links, or you might just hide them on your website. You can always just go to http://(yourname).gositepress.com/wp-admin/ to login directly.
And if you can’t remember anything else, you can start at http://gositepress.com.