Security expert Alan Woodward offers this advice:
• Don't choose one obviously associated with you: Hackers can find out a lot about you from social media so if they are targeting you specifically and you choose, say, your pet's name you're in trouble.
• Choose words that don't appear in a dictionary: Hackers can precalculate the encrypted forms of whole dictionaries and easily reverse engineer your password.
• Use a mixture of unusual characters: You can use a word or phrase that you can easily remember but where characters are substituted, e.g., Myd0gha2B1g3ars!
• Have different passwords for different sites and systems: If hackers compromise one system you do not want them having the key to unlock all your other accounts.
• Keep them safely: With multiple passwords it is tempting to write them down and carry them around with you. Better to use some form of secure password vault on your phone.