The 5 things that made me go from losing money to becoming a profitable trader

1. Understanding how the market is basically all math, not vibes. When I was 19 I used to actually pay attention to technical analysis and think stuff like support and resistance is what matters. In reality, pretty much most TA is a complete waste of time and any serious trader knows this. There's a reason why TA gets clowned on so much – it isn't a good way of modeling markets at all.
2. Going from discretionary/fundamentals based trading to quantitative trading. This was the biggest game changer and when things just began to click. With quantitative trading, you can actually find real edges in the market that repeat themselves. You can analyze millions of data points and see exactly what works, why it works, and if it is likely to continue working. If you aren't backtesting your strategies with data, you basically going in blind.
3. Reading research papers. If you want to become a profitable trader, I think the biggest predictor of success is obsession. Because you are competing against people who are truly obsessed with the markets. If you aren't obsessively reading research papers and trying to learn what makes a good edge in the market, you're unlikely to find a breakthrough.
4. Using other people's strategies as a point of learning. Before I made my own trading engine, I used to study strategies such as David Sun's Theta Engine and drew a lot of inspiration from them. I began to understand how volatility works and how there is an edge in short volatility strategies. Trying to do everything from scratch is unlikely to be a good use of time in the start. To that end, if you guys want to see what strategy I run and draw inspiration from it, check my profile.
5. Automation. This is the final and most critical piece of the puzzle. Without automation, it's impossible to have completely emotionless and repeatable execution. It's impossible to enter the same setup the same way each time, without letting fear and greed get in the way. This is the piece that most people overlook. Almost every broker has an API now and if you're still trading manually, it's probably not a good use of your time. You should be devoting your time to building profitable systems, not executing trades manually and staring at the charts all day.

That's my 2 cents. Let me know what made you profitable (or unprofitable) trading options.