How do you hold a paintbrush for oil painting

I have a complete demonstration of this process on the How to Paint a River Tutorial – part 2 – approximate minute 19:30. I am using an Ivory Short Flat brush #1 with no thinner or Liquin in the paint. I load the brush on both sides by pulling down in the pile of paint, then by holding the brush on a 45-degree angle down and 45-degree angle away from the panel. I touch only the tip of the corner of the brush – flip over and touch the other corner – only touch 2-3 times per corner and reload the brush. The overall pattern of the strokes is to create the shape of a tree and leave space between each one.