Blind contour is a drawing practice that focuses on improving hand-eye coordination. It is usually done in pen and in one continuous line (though sometimes I’ll add in a few details after the practice is done).
While not all of my drawings are done in this fashion, many of them are and it is one of my favorite life drawing techniques. When you do it a lot (like, a LOT a lot) you’ll start to see that the people you’re drawing are looking more and more like the actual people, rather than just scribbles. The trick is starting out slow and focusing on staying on the page, while filling up the page at the same time. Try it for yourself! Though you probably shouldn’t spy on people like I do until you get good… people like to see what you’re drawing and do not take kindly to scribbles when they expect masterpieces :p