Spend bitcoin on goods and services directly, then it will not become a taxable event, then you will be able to spend it and avoid taxes and maybe even bitcoin will grow even more before you spend it all 
This is NOT true in the U.S.A.
In that country, spending bitcoins on goods and services directly IS a taxable event.
Or if you really want to exchange it to cash, you can do it via some other good, like gold for instance, chances are it will not be a taxable event either.
This is NOT true in the U.S.A.
In that country, exhanging bitcoins for some other good or asset IS a taxable event.
Having spent a lot of time working with our tax accountant (USA) in 2017 and 2018, I can confirm that spending or trading BTC for other assets is indeed a taxable event.
Spending or trading BTC is typically seen as a Capital Gain (in the eyes of our IRS).
Doing the work is tedious, and usually requires records of BTC buys and sales (trades).
Do as Danny suggests, consult a tax pro. Dont ask for trouble.