For me, going to hear an artist speak is a crap-shoot. You can find great, enthusiastic professionals who have a clear-cut outline and move easily through the subject matter or you can find stumbling, "uh...uh" types who are winging it and look pretty doltish.
I would suggest finding out how long the session should be and then loosely scripting your talk with some bullet points to keep you on track. Practice giving your talk to a friend or relative to make sure it times out correctly.
I would divide the talk into three sections:
1. Brief history and current status (10 minutes or so)
2. What inspires you and what your process is about. (15- to 20 minutes)
3. Questions and Answers. (Appx. 15 minutes or until the questions run out.)
This is usually just long enough to make sure your listeners' eyes don't glaze over. The questions and answers section can be fun if the audience participates
so it's up to you to garner that participation. Having it at the end wakes up those who are on the verge of a nap.
I've done a few of these in the past, but preparing ahead of time really helps. Whatever you do, don't try to wing it.