3 Ways of starting a portrait painting

I have noticed I have 3 ways of starting the painting:

1. With a sketch 
2. With sketch + under painting
3. „Blind” painting

With a sketch-  I would start with a detailed sketch (making sure all sizing is correct and in place before I start) and put the paint directly on unpainted canvas. For me this works if its a small painting and I don't want to spend time waiting for under painting to dry. You can see the you tube video on the post Painting A little girl or Inspired by Game of Thrones. 

With a sketch + under painting - I have noticed that I like to do under painting for bigger portraits. This I usually do in acrylic as it dry much faster than oil under painting. I like to choose burnt umber or burnt orange for under painting as it gives warmth to the portrait. Sometimes green or paynes grey is good too to bring out the pink and orange top tones. Under painting also prevents the blank canvas from showing if the canvas is not fully covered. It also gives you an opportunity to establish the darks and lights early. Usually I use this this technique for commission work. I have posted an under painting on you tube for the portrait seen in previous post. 

,,Blind” painting - I just call it that way. Not sure if there is a proper term for it. It simply means that I paint directly on canvas - starting with vauge shapes and adjusting as I paint. I love the creative process of it, but it is much harder to get likelines of the person. I guess it takes practice and eventually one gets to know where to look and what features to enhance to achieve liveliness. If I work on a commission piece its very unlikely that I would use this technique as in many cases it would take longer to fix the mistakes than doing the detail sketch in the beginning.   Positive- it gives more room to play around and thus can make more interesting art piece.

„Blind” painting technique used on this portrait