Does DCA here have to be supported by stable finances? for example, having a steady income from work which can later be used to invest more regularly.
I'll answer it for you but based on what I understand, so don't swallow it whole so you have to decide for yourself.
The first, is DCA or stands for Dollar Cost Averaging, which means saving regularly. Ideally you should have a stable income, if you work and get paid weekly or monthly then the percentage of Bitcoins should be taken into account. For example, if your monthly salary is $300, then 10% is used to buy Bitcoins, withdraw whatever you want to a cold wallet and remember, don't store your Bitcoins on centralized exchanges like Binance, KuCoin, Mexc, etc. According to your goals, you want to hold Bitcoin in the long term.
Second, if on the other hand your income isn't as stable as your friend's but you keep investing in Bitcoin, it's just that your buying patterns may be erratic depending on whether you have the money or not at the time. Is that bad? Of course not because basically being able to buy one is already a good decision whether you want DCA or not. Because the most important thing when buying is to make sure the bitcoin price is in a bearish trend or a red candle.
What do you think the ideal DCA looks like? I really need advice because I have been studying Bitcoin for a long time, my income is quite stable for now. It would be very profitable if this financial allocation was invested in Bitcoin. As long as I know the risks, I believe Bitcoin will be useful in the future and institutional adoption is also currently increasing. As someone who is interested in investment strategies, you definitely need the right method.
Third, here it seems like you already have pretty good basic knowledge about Bitcoin plus you already know what the risks are when investing. I think it's enough as the main foundation, it just needs to be executed in my opinion. Because you already know the risks and already have a steady income compared to your friends' conditions, you may be able to collect more Bitcoins more quickly.
Just a note for you, the idea behind DCA aims to educate investors to have disciplined habits in order to achieve bigger goals in the future. Hopefully this can help and strengthen your determination in investing, the pros and cons of the explanation above, please only take the positive side. I, you, and everyone are still learning so don't be shy to ask questions and keep reading more from reliable sources about investing so you don't lose money by mistake.