I have switched to TIG, but still sometimes have the same problem when I get in a hurry. A good welding mask is a great help. With steel, you can sense the temperature of the weld pool by the color. You want to keep the puddle of molten steel small and not too hot. Very generally, the puddle, ie. the part that is yellow to white hot should not be more than something like 2-3 times the metal thickness. The larger the amount of fully molten metal, the easier it is for some of it to just fall on the floor. If the weld puddle gets too big, you can back the electrode away, or speed up the progress across the seam.
With stick, I was not able to fill holes easily. With TIG and a pedal control, I find it a lot easier to build metal up on the edge of the hole and fill it in pretty quickly. I'm still learning, myself.