To change your blog's title and tagline first go to "settings" on the bottom left side of your Wordpress blog page. 

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Once there you will see "Site Title" and "Tagline." 

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To change them, all you need to do is click inside the text box and then make any adjustments you want to make. 

Before you leave the page, don't forget to click "SAVE CHANGES" at the bottom of the page.
 

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