To change the look of the blog without editing the CSS, you'll have to download and apply a new theme. There are many available here-
Developers often make themes so you can probably Google 'Wordpress themes' and see what comes up.
In order to change the URL of the blog, first make sure the new domain name is pointing to the site, then do the following-
1) Log into the admin
3) Change 'WordPress address (URI)' and 'Blog address (URI)' to what you'd like the new URL to be.
4) Hit 'Update Options'
That should do it. Again, make sure the domain name is pointing to the blog or the change will render to blog inaccessible.
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