A compost pile works best when it is moist enough for microbes but not saturated. Checking the center of the pile gives a better reading than judging the dry outer layer.
Turn a small section
Use a garden fork to open the pile safely. Look for dry brittle material, soggy clumps, and a balanced mix of leaves and green material.
Use the squeeze test
Squeeze a handful of mixed material. It should feel damp, with little or no water dripping out.
Adjust gradually
Add water in a light spray if dry, or add dry leaves and turn the pile if wet. Avoid flooding the pile.
Recheck after weather
Cover the pile during prolonged rain and inspect airflow. A balanced pile should warm and break down without a foul smell.