If these are something you'd like to watch and learn from, here's a link to their youtube channel. Scroll down and look for the 3rd Thursday videos. (There's a lot more great stuff to learn from, too!) And they offer very reasonably priced classes to learn professional techniques.
And since blogposts are boring without something visual, below is a recent page from my sketchbook. Which leads me to ask, have you sketched today? Fifteen minutes a day can go a long way. (Hey, I sound like one of those commercials out there . . .)