If borrowing money, negative real interest rates, and now also printing money by quantitative easing, actually worked, we would now have a thriving economy, as we have followed these policies since 2008.
So perhaps doing the opposite is the answer. Stop printing money and stop borrowing it. Debt never made a nation richer. Give savers an incentive to provide money for investment by giving them a decent return.
Slim the public sector, whose bloated excess is unaffordable now, and will be more so as its huge pensions liability kicks in.
Simplify and reduce taxation, direct and indirect.
Break the crippling bonds of State Britain and give people the chance to create a Great Britain.