But Refinery29’s financial expert Priya Malani is here with some calming news: the best thing you can do is nothing. You can’t access the money in your 401(k) until you’re 59-and-a-half years old, and that “long-run” money will run into challenges through the years that it will be able to recover from.So, her professional opinion? “Don’t tinker.” Trying to sell or move around assets now is a losing strategy that will backfire over the long run.In fact, if you can afford it, Malani says now is a great time to buy, either for your 401(k) or other investments. Essentially you’re buying the stock market while it’s “on sale.” She also cautions that there’s no huge rush. "This dip will roll out over the coming months,” she explains, so you can invest slowly over the course of weeks.For more investing advice, check out our primer to investing And if all else fails, just try this mantra: