We have dreamt of a 5 trillion dollar economy, it sounds difficult. But if we do not aim high, how will the country progress?
Who is trying to have a $5 trillion economy? The US already has one, as does China. No other country does as yet.
So, obviously, start with lots of people. Then what? Well, probably have a free market and capitalist economy. Then wait.
Other than that there’s not all that much to it.