Why six profitable months on small money is the right bar before sizing up, what "small" means, and how to scale afterwards without blowing up.
One profitable month proves nothing; markets have two- or three-month moods, and a strategy that fits one mood looks brilliant until the mood changes. Six months crosses at least one regime change, which is where most strategies die. If yours survives it, you have learned something real.
An amount whose total loss changes nothing in your life. For some people that is $5,000; for many it is $200. The lesson is identical at any size, because the lesson is about your behavior, not the market's.
Then do the six months on paper, with live prices, real liquidation rules, realistic size, and the same journal. Treat it as if it were real: if you would not have taken a trade with money, do not take it on paper. A simulator that resets daily, like RektChat, is useful here because it prevents the quiet trick of hiding a blown week inside a lucky month.
After six green months, increase size by two or three times, not by twenty. The habits that got you here are size-dependent; some of them will not survive the first larger drawdown. Scale slowly enough to find out gently, and keep the daily loss limit proportional as you grow.