When I began the process of learning to train serious skills for defensive handgun applications, I think I wasted a great deal of time and money by not getting quality formal training immediately. Eventually, I traveled around to train with some recognizable instructors, but I learned most of what I know today from the internet and books. Good initial training from a QUALITY instructor is certainly ideal (they are not all created equal, unfortunately). That being said, I think there are some things that really helped me out more than others.
Trigger Finger Register Position
Craig Douglas about trigger finger register position:
https://www.youtube.com/watch?v=1asDqdVoH-U
4 Count Drawstroke
One of the most simple and important things, to me, was learning the 4 count drawstroke as taught by Craig Douglas or the late, great Paul Gomez (RIP). I suppose you could refer to this as a ShivWorks 4 count draw. Even if you're not planning on concealed carry, I think learning this format of working from the holster is invaluable, and it can be done without live ammunition. It serves as a strong fundamental basis of basic gun handling in a very simple, regimented and prescribed format. This basic scheme of motion helps to tie Coopers 4 Rules of firearms safety to an unambiguous, embodied practice, and it can be drilled if you have even one minute of spare time and an airsoft/dummy prop gun.
Paul Gomez-rapid explanation of 4 count drawstroke
https://www.youtube.com/watch?v=7OZfgutNufU&t=1s
Craig Douglas-deeper dive into drawstroke counts 1,2,3 and 4:
Count 1
https://www.youtube.com/watch?v=XEBVimrZ4b4
Count 2
https://www.youtube.com/watch?v=-dOXCChdw-w
Count 3
https://www.youtube.com/watch?v=dHmpHNTWXTE
Count 4
https://www.youtube.com/watch?v=I2qGyIxed9Y
Craig Douglas-some additional videos about drawstroke:
https://www.youtube.com/watch?v=zqnaoI11YpA
https://www.youtube.com/watch?v=iZwYmNwlVi8
Positions for Muzzle Aversion-Arc of Ready
Another conceptual framework, and simple embodied scheme of motion, practicable without shooting, may be well described by Dave Spaulding's phrase "Arc of Ready". For me, these simple concepts, themselves movement practices, compliment and dovetail into the ShivWorks style 4 count drawstroke perfectly. Although I prefer the nuances of how Craig Douglas of ShivWorks teaches some of these positions, Dave Spaulding's phrase, and some of his explanations about how/why such a scheme of motion is useful, have been very valuable to me in understanding these ideas.
Paul Gomez on Ready Positions and Positions for muzzle aversion:
https://www.youtube.com/watch?v=ftC6MXFGxCg
https://www.youtube.com/watch?v=NLMesZVCZdw
Dave Spaulding on Arc of Ready/Positions for muzzle aversion:
https://www.youtube.com/watch?v=6faxyKh7QZ4
https://www.youtube.com/watch?v=LetQfjmaJOw
Dryfire
The regimented practice of a robust 4 count drawstroke can be combined with inert training rounds, such as these
https://stactionpro.com/product/9-mm...r-dummy-round/ , in a Glock 19 or any other 9mm handgun. They can be used to practice load/unload/reload skills that promote SAFE, combat effective gun handling skills.
Dry fire drills combined with the 4 count drawstroke can help you learn shooting mechanics. However, without live fire recoil for feedback, it's possible to build and ingrain very bad habits. I think one thing that helps me here is to think of gripping the gun in dryfire as a strength training exercise. I want to be gripping hard.
Claude Werner, "The Tactical Professor", has a website and online articles/courses/ebooks that address dryfire and protocols, mindsets, decision making and avoiding common mistakes, at a very practical level. I consider him to be an indispensable resource for any new gun owner thinking about defensive use of a handgun.
https://thetacticalprofessor.net/
So, in conclusion, if I were going to go back in time, I would tell myself to get some proper training straight away. Failing that, or in preparation for it, I would tell myself to watch all of the videos on Paul Gomez's YouTube channel in reverse order (oldest to newest), and become obsessive about studying all of the Craig Douglas/Shivworks content I could get my eyes/ears on. I would also take a deep dive into Claude Werner's Tactical Professor content with regard to avoiding stupid mistakes and how to think about dryfire and practice. There are many other great resources available, but this is where I would start. Also, everyone should read The Law of Self Defense by Andrew Branca, and everyone should be exposed to some of Massad Ayoob's content about legal considerations and related context about what may happen after a self defense encounter.
You can do this if you approach it with serious work ethic and reverence for learning an Art. Practice embodied drills for at least a few minutes each day, but pay particular attention to the nuances and specifics. Practice does not make perfect if you are practicing imperfectly; in that case you are just deeply ingraining bad habits. Be very thoughtful and take a quality over quantity approach in the beginning. You will do well if you want it bad enough to seek the knowledge and invest your attention in the correct areas. You have surely come to the right place to start!