You will normally see many of us recommending lots of practice on a new airbrush before trying it on a model! Airbrushing is not an art acquired just be reading about it. It is more like learning to ride a bike or learning to play tennis.
Can't help with the dropping of stuff on the floor, though. For me it is just part of modeling. I even have a lap apron fastened to my workbench, but forget to drape it over my knees until AFTER the tiny part (usually model part) falls on the floor. Yes, I am constantly closing barn door after horses escape!
Also can never remember to replace drill press chuck key on its storage magnet. Always have to look all over workbench for it, even after having a drill press for 25 or 30 years!
Funny, I can learn new modeling techniques (PE, Alclad, etc) but not the old standard shop practices :-(