My goal is creating and delivering a program which creates a memorable audience experience this time and a better one next time. To improve I want to know how well I performed and what I could do better. I want the answers to three questions:

After seminars and workshops I ask participants to complete a quarter sheet form with these three as sentence stems.  While this is seldom convenient after a speech, I can glean these points from those who want to chat after.  (The dashed arrows in the 4-DEEP loop are a reminder that Debriefing is seldom done. Take the time to self-assess, honestly.) 

Important Note: I do not seek negative comments (they will come).  By focusing on the positives — what they liked best, what they want more of, what they want added — the superfluous material will disappear as it goes unmentioned. This works for me. Create a personal debriefing process.