Lettering Basics: Brush Pens and Pen Pressure - 2/3
У вашего броузера проблема в совместимости с HTML5
Be consistent with your lettering by using your entire arm rather than just your fingers and wrist.
Read the full blog post here: http://hghplp.co/1pB3PIu
List of pens and other resources here: http://highpulp.com/resources