The recommended strategy is to continue dollar-cost averaging (e.g., buying the S&P 500 weekly) even when markets are down, without changing the strategy.
"if your strategy is dollar cost averaging every week you're putting money into the markets you're buying the S&P 500 every Wednesday you buy the S&P 500 then what do you do when the markets go down you keep buying the S&P 500 you don't change the strategy"