Alternatively, you can sell a covered collar that protects your downside enough to know that you'll have the cash on hand come tax time. This limits your upside somewhat, but usually less than selling the stock outright. Mark Cuban famously used this strategy to protect his Broadcast.com payout under lock-out.
(Check the details of your contracts with an attorney and financial advisor; I've heard that some lock-outs now explicitly forbid trading in derivatives of the stock to prevent doing what Cuban did. With financial engineering being as advanced as it is, though, it's always possible to create a "synthetic" derivative that is nearly guaranteed to have the same value as a particular options strategy without mentioning the particular asset involved.)
Trading options against employer's stock may be forbidden by insider trading policy. It was in my previous job (along with shorting, and only trading during trading windows). Can't say I disagree with such policies.
Other than that yeah, get a collar or just straight up buy some puts. Or like others recommended - sell some % instantly and put in high grade bonds, or a savings account. Forgetting taxes is a big mistake.
https://www.acceleratedfi.com/real-world-options-example-how...
(Check the details of your contracts with an attorney and financial advisor; I've heard that some lock-outs now explicitly forbid trading in derivatives of the stock to prevent doing what Cuban did. With financial engineering being as advanced as it is, though, it's always possible to create a "synthetic" derivative that is nearly guaranteed to have the same value as a particular options strategy without mentioning the particular asset involved.)