You can quickly adjust the ad layout using the ad layout / output options on the ad edit screen.
With the layout options you have some features to position the ad in your content without touching any code.
With the position option you can align ads within your content even float other elements around them.
Use the clearfix option below the alignment options in case you only want to align the ad but not float text around it or you experience some interference with following elements.
The margin option allows you to add some distance to other elements. For example in the image above you find settings that align the ad on the right and float the content around it, but also sets some margins to the left and the top. See the following screenshots to compare the result in the frontend.
For the features above, the ad code is practically wrapped in an additional block ( div ) and inline styles.
The clearfix option adds a <br/> tag with inline styles behind the wrapper.