AMGA Certified Rock Instructor Erik Kramer-Webb shows how to give a direct belay for the follower once you have led the trad pitch. If your blocking carabiner is fat and round the rope will pull easier. An ATC Guide or a Reverso is known as a "plaquette" device and will typically self-lock under the load of the falling climber. Since there are circumstances when it might not self-lock, we must always be ready to brake manually. Be sure to learn how to release a loaded plaquette. Ryan Huetter has a nice youtube video on that subject. Look him up. He is rad. You will notice that I tie a two-handed clove hitch, standing on a ledge. If you have to build an anchor from an insecure stance, you can clip into your first piece of pro in your anchor with a quickdraw, then build the rest of your anchor, and then tie in with a one-handed clove hitch.