There are hundreds of themes designed by WordPress developers and users that you can choose from to change the appearance of your site.
To change your theme you need to access the ‘Appearance – Theme’ screen from your dashboard.
Click the ‘Activate’ button under one of the themes to quickly change your theme.
You can then see what it looks like by clicking your pages name in the top toolbar (under ‘My Sites’) and selecting ‘View Page’. You will notice that the information on your page remains the same but the appearance has changed. Some themes will work better than others depending on the purpose that your site has, so check out a few before you decide, you can always come back and change it again later if you still can’t decide.
To learn more about themes, hover over one and click ‘Theme Details’. There will be lots of information such as what the theme was designed for and details about its functionality.
You can customise the images, colour scheme and fonts to suit you at a later date (see the tutorial page ‘Customising’) so pick a page theme based more on it’s functionality rather than aesthetics. If you like a themes layout but not it’s images then you can change these later, however, if you like a themes images but it’s menu system doesn’t suit your page then this will be more difficult to change.