I read a lot of posts on this topic. People offer any, even fantastic options. Each of them has advantages and disadvantages.
I found a simple and understandable solution. We have Private Key, for example
ch74nhcwrf4439nfv340fvq3rvn23mf2fj20f204f
You can leave it on the computer + print and put somewhere at home + make another copy on the email.
It is necessary to do only one thing. Change 4-6 characters.
For example, change ch74nh to krw49d Further, it is enough to remember these 4-6 characters.
Now if a hacker gets access to your computer and finds a Private Key, he can not steal money.
But we can do even better. Replace characters not at the beginning of the Private Key, but somewhere in the middle. For example, the date of birth your wife on 12 December. You definitely will not forget this date. We change the symbols from 12 to 17.
My brother I want to use this opportunity and time to thank you for the wonderful and amazing information you have given us. The above information is very helping to us. I would personally implement what you have told about the security of our wallet and our private keys. Thanks for your great suggestions.