What to do before then? Don't have any money in US stocks. Diversify both geographically and sector-wise, cash out, be ready to invest when stocks crash through the floor, to ride the wave when they inevitably rise again. The real trick is spotting who's going to rise again and who's going to be left behind. Tech stocks are volatile by nature, invest in renewable energy and related sectors. We're going to need solar and wind power in the future, and batteries. Lots of batteries. Then, as we near battery saturation, there is going to be big money in recycling all those depleted batteries.