I have the password to my wifi network set as a 128 digit hexadecimal number - no one’s getting on for free.
A good way to generate passwords for a wifi network is to use the sha256 hash from an easily reproducable file.
$ echo "this is my pass" > mypass
$ sha256sum mypass
857571d81ecdbb959b686bb167bb2b49ff0aecf0c379d1da84df6b8eac254090 mypass
Or you could just echo a phrase you can remember through sha256sum
echo "this is my password" | sha256sum
90d47cbbb1372717ab2bd56b94389665d58900bee14dc8199ea6a239b24a702b -
This way you don't have to ever write anything down, yet you have a key you can reproduce at will.
Anyone trying to hack your wifi is going to have to do a brute force attack against the entire address space because your key doesn't decrypt to an actual typable password.