When I arrived at the seminary I was the youngest on campus and one of the weakest in Arabic. Three years later I was the one teaching grammar to the other Western students. People assume that is talent. It was not. It was a method, and the method works for anything: a language, a business skill, a craft, a faith.
1. Learn in public, early and badly
The single biggest accelerant was that I had no choice but to use what I was learning immediately, in front of people, while I was still bad at it. Every Wednesday night we gave lectures to each other and got picked apart. It was uncomfortable and it was the fastest teacher I ever had.
Most people do the opposite. They study privately until they feel ready, and "ready" never comes, because the confidence they are waiting for is only produced by the exposure they are avoiding. Use the thing in week one. Be bad in front of someone. The embarrassment is the tuition fee.
2. Teach it before you have earned the right to
I understood Arabic grammar properly the day I had to explain it to someone else. Teaching forces you to find the holes. You cannot bluff your way through a student's honest question, and the questions you cannot answer are a precise map of what you do not actually know yet.
You do not need a classroom. Explain what you learned today to your wife, your mate, a voice note to yourself. If you cannot say it simply, you have not learned it, you have only met it.
3. Volume beats intensity, but only if it is deliberate
We studied twelve to fourteen hours a day, but the hours were not the secret. Plenty of people sit with a book for twelve hours and learn little. The secret was that the practice was effortful and specific: not "read Arabic," but "conjugate these ten difficult verbs until I stop making the error I made yesterday." Practice aimed at your current weakest point, not your comfortable strength, is worth ten times the reps.
4. Get one mentor closer than is comfortable
In the early days there were only twenty of us, which meant daily, face-to-face time with the Sheikh who ran the place. That closeness did more than any curriculum. A great mentor does not just give you information, they show you the standard, correct your specific errors, and believe in a version of you that you cannot yet see.
You cannot always engineer that proximity, but you can stop hiding from the people who are better than you. Sit near them. Ask the question you are afraid makes you look stupid. The discomfort of being the least capable person in the room is the price of the fastest room to be in.
5. Let it cost you something
I funded my study labouring on Sydney building sites every summer. I told my family I would sell my phone, my bed and my clothes before I asked anyone to carry me. I am not romanticising hardship, but I have noticed that the things I learned while they cost me something stuck, and the things that came free mostly did not. Skin in the game focuses the mind. If a course is free and optional, you will treat it that way. Put something on the line, even if it is only a promise to someone you respect.
None of this is clever. It is learn in public, teach early, practise your weakness, get close to a master, and pay for it somehow. The reason most people do not learn fast is not that they lack the method. It is that the method is uncomfortable, and comfort is the enemy of speed.