In the past, hackers have analyzed passwords collected from large-scale breaches in order to build tools that can be used to anticipate the patterns of passwords that people frequently use. Many people, for example, will incorporate the name of their dog and/or the four digits of their birthday so it won't take many tries to break in. Instead, try stringing together a few words that don’t bear any relationship to one another.
It’s best to have passwords that are at least 12 characters long with special characters or capital letters scattered throughout. So, for example, if I were to set a password for my Nest account I might try "almond,Dream!tidy." I selected three words at random and added special characters and capital letters with no identifiable pattern. According to Dashlane's password tester, it would take someone 610 trillion years to crack that code.