Another thing to remember - rebounds are highly compressed. If you try to get out ahead of a downturn, you will not only likely mistime your exit but also miss the rebound. It can keep going down or stay flat for sometime. But when it rebounds, it does so quickly [1].

Don't try to be too smart. Especially if this is not your full time job. The market is not rational. Dollar cost averaging and proper risk allocation is the way.

[1]https://www.hartfordfunds.com/practice-management/client-con... & https://www.fidelity.com/learning-center/wealth-management-i... (if you prefer an additional source)