People who try to time the markets tend to lose big time. Buy good stocks or funds and hang in there. Over time, the stock market rises something like 10% a year. Individual years fluctuate. One year might be 2%. The next year might be minus 8%, the year after that might be up 14%. But it averages out nicely.
I happen to have an excellent financial advisor who has done very well for me over the years. He has me in various funds, not individual stocks. Some years back he had me buy two annuities (which are generally swear words here because people don't understand them) and I've been taking income from them for a while now. I cannot outlive these annuities. If I die while there is still value there, my beneficiary will get the residue. If I actually live long enough, and if their investments aren't so good, I will still collect my guaranteed income.
I do want to reiterate that trying to time the market is a losing proposition. Buying good stocks or funds and staying with them long term is best. Also, there are various ways to invest. You absolutely want to be diversified. Meaning you want to be invested in different kinds of funds (or stocks if that's your preference) that include many different kinds of industries and such.
Were I investing on my own these days, I'd look closely at stocks that pay dividends. There are lots of them out there. I bet there are mutual funds that invest in those kinds of stocks.
But back to your question, stay in the market. You might possibly want to do some selling to realize cash and then jump in to buy at a downturn, but that's a version of timing the market, which is rarely a good strategy.
Honestly, I am financially secure because of buying and holding.
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Not sure I understand how they work 
-- sounds complicated!
