I had to redo it 2 times in order to get a base head that was suited to continue with.
My first approach was drawing single vertices at the front of the face and then adjust their depth with side view. At some point I found it to tedious to identify and map the individual dots from the side view to match the depth so I discontinued that approach. It was also already too detailed for the base head:
My 2nd approach was starting from a ico sphere and use sculpturing tool. For some reason my base head was not 100% symmetric so I could not use “x-mirror” during sculpting because it was applied differently to both sides. I tried to do both side sculpting manually then. The result was a not really symmetric face 
And again too detailed for a base head:
And here is my 3rd approach (like in the tutorial) which I will use to continue with:
