Nightly reflection is a relaxed meditation that is done right before going to sleep. I do it lying on my back in bed with my hands folded on my stomach (this called the "corpse" position in yoga). The eyes can be open or closed. It's best to do this at approximately the same time each night, and it's especially important to do before getting too tired.
The intention of nightly reflection is to review the events of the day, starting from the first memory of morning to the moment you begin reflecting. Focus on the main events, thoughts, and feelings you've experienced throughout the day, as if you were watching the highlights of a movie. During nightly reflection, it's important not to get pulled into thinking and analyzing, but instead to review what actually transpired as objectively as possible, without getting caught in judgments. The instruction is to try to stay physically grounded by maintaining awareness of the breath passing in and out of the center of the chest. Without this grounding, the exercise can easily become too mental.
Once the review if finished, ask yourself two questions: "What am I most thankful for?" and "What do I feel the most remorse for?"
— Ezra Bayda in Zen Heart