One good but not too difficult-to-use solution for more secure passwords is to use a browser plugin like "Password Hasher". When you have to input a password, it asks for a "master" password, which is then used to generate (through a one-way hashing algorithm) a different password for each website (based on the website name).
You only need to remember the master password, and the plugin does the rest. If one of the websites is compromised, and your password for this site is leaked, nobody can use it to log in on another website. And you can generate a second, different, password for the same site with the same master password (using the "Bump" button).
Try "Password Hasher" for Firefox, "Password Hasher Plus" for Chrome and "Hash It!" for Android (they're all compatible as in they generate the same unique passwords for the same input).