When using live rates, you may want to include a free shipping option for customers who reach a certain threshold - like a certain number of products, or from a certain country.
Under 'Shipping' in the administration, check 'Use custom' and 'Free ground shipping' under 'Custom Options', and update the settings. You can also rename it to be whatever you want from within the 'Languages' section of the administration.
Paste the following code right before the closing
</head> tag of your checkout template, updating the logic to match what you're checking against: