A strong password is your first line of defense against unauthorized access. Most people use passwords that are far too short or far too predictable, and many use the same password across multiple accounts. If one of those accounts gets breached, every account using that password is now at risk.
The best approach is to use a password manager to generate and store passwords automatically. A password manager creates long, random passwords for every account and stores them securely so you only need to remember one master password.
If you need to create one manually, combine three or four unrelated random words into a passphrase, then add numbers and symbols. Something like coffee-ladder-river-72! is long, memorable, and far harder to crack than a short complex password like P@ss1!.