How to write 8 health code registration passwords and 12 passwords?

I would like to ask how to write the health code registration password with 8 to 12 digits. Password setting generally requires 8 digits to 12 digits, such as abcd 1234 or zji 123d8396.

Precautions for password setting 1. There are the following combinations: uppercase letters plus numbers, lowercase letters plus numbers, numbers plus lowercase letters, numbers plus writing letters, numbers plus lowercase letters, and uppercase and lowercase letters plus numbers. 2, password settings must have a simple way of remembering, otherwise it will be very troublesome when you forget the password. 3, the password should not be the same as several passwords. After being known by others, try to reduce losses.