How can you tell if farm eggs are old?

How do you accurately determine the freshness of farm eggs? Are there any tell-tale signs or methods to use when examining the shell, color, or even the interior of the egg to assess its age? It's important to consume fresh eggs for their optimal nutritional value and to avoid any potential health risks associated with older eggs. Can you walk us through some practical steps to ensure we're buying and using the freshest farm eggs possible?