If you can choose between more than one airport, choose the long distance international one for long weekends and the short haul domestic one for long vacation periods.

Here is the example, on July 4 weekends out of NY, JFK is empty but LaGuardia mobbed. Most people are traveling for 3-4 days short distances from LaGuardia. So if you can find a flight from JFK to your destination, use it for a less crowded terminal experience. On traditional longer holiday period like Christmas / New Year the opposite might work out better.

Especially for women traveling who find terminal bathrooms a mess, try to find the least crowded airport.