At this point I don't have too many tips on learning the bandoneón, but as I learn I will share any little gems I have here in hopes that they may help others learn faster. I'm sure some will seem obvious, but still having someone tell me has helped me along the way.

Tip 1: Practice Scales and Arpeggios every day.

Learning to play all of your major, minor (at least harmonic minor) scales and major, minor, dominant, and diminished arpeggios with both hands, striking the keys with weight in your fingers, slightly separated notes, and with constant airflow, will be the most useful 1000+ hours you will spend with your instrument. Its painful, it will give you headache, you'll wonder why you even decided to play the bandoneón but do it anyway and you will see tremendous results (and eventually you will understand why... but don't expect to understand in the first week, or month....).

Tip 2: Do everything you can with only your fingers.

To play well, and to be able to relax your wrists, you have to learn to articulate notes from just your fingers. There are many exercises to help you achieve this, the one that worked the best for me was to play a scale repeating each note first 2 times, then 4 times, then 8 times. After a few days/weeks of this you will start to notice that your fingers are gaining independence and working on their own.

Tip 3: Relax your wrists!

Relaxed wrists are essential to playing fast and to having a good sound, but it is very hard to achieve, especially before achieving tip #2. A lot of what you hear in your fist 2 years of lessons is "relax your wrists". It improves your sound dramatically and gives you much more control over the instrument. Always check to make sure your wrists are relaxed.

Tip 4: Play out.

Polenta! Don't practice quietly or you'll never be able to play loud. play out but keep wrists relaxed (I'm serious).

Tip 4: Everything takes practice.

You want to play fast? You have to practice playing fast. You want to play loud? You have to practice playing loud. Nothing just happens, and everything on the bandoneón has to be practiced, but the good news is you can learn anything (seriously anything) if you practice it efficiently and consistently. PS. if this inspires you to practice speed, make sure your wrists stay relaxed. (seriously.)