What Makes a Good Password
Length and complexity are what constitutes a strong password. But keep in mind a long password with no complexity is useless.
Go test the stength of some passwords here at this website http://www.passwordmeter.com/
Tools to Manage Passwords
Keep in mind that using a password manager apps is handy and they might use good encryption to keep your info private you are still giving a third party all your really imponrtant information and there for some risk is accepted.