First, we can tell whether the airport has a control tower or not, just by looking at the symbol. A magenta symbol indicates that an airport is non-towered, while a blue symbol indicates a tower. For this lesson we are only interested in the non-towered, magenta airports.
When figuring out if the airport is suitable for us to use, the first thing to look at is runway length. An airport with a solid circle and runway depictions inside indicates the longest runway is 1500-8069 feet long. An airport diagram that looks like a runway without a circle around it means that the longest runway is longer than 8069 feet.
Tick marks around the diagram show fuel services and other services are available from at least 10:00am to 4:00pm Monday-Friday. A star at the top of the diagram indicates a rotating beacon.
All other airport information is listed next to the diagram. This includes the airport name, identifier, weather frequency, elevation, longest runway length, CTAF frequency, and other notes. While you can get almost everything you need just from the diagram, it is also important to check the airport/facility directory before you go. This will give you any other local information you need to know.