Every artist has their own process when it comes to creating artwork. I came across these two films on YouTube while researching. It's very inspiring to see other artists amidst the act of creation.
Michael Shapcott is an artist from Central Connecticut who creates beautiful portraits. Shapcott has many videos on his YouTube channel that document his art making process.
Daniel Conway is an artist from the UK who creates magical, surreal landscapes and portraits. You can find out more about Conway and his artwork at his deviantART page.