Re-balance your portfolio back within the exposure level you are comfortable with.
(Remember Your investment strategy must be well reasoned, suit your tolerance for risk.)
This is how you sidestep the majority of the capital destroying losses.
It also leaves you with sufficient capital to bring to the bear market too.
If there is a Bull, there will be a bear...!
note: None of my posts are intended to imply any form of buying/selling advise.