There is a very simple process.
Think of a person, a place or an event. Think of something you associate with that. For example, what you remember most about your ex Jen is: "Jen and I made out in the back of the car" The password become jaimoitbotc. You can embellish that by throwing in numbers and capitalization based on some formula. Maybe every 2nd, 4th, 8th and 16th letter is capitalized. Every vowel is replaced by a number, like a=1, e=2, i=3, o=4,u=5.
The password now becomes: j13M43tB4tc
The best part is that you can put a sticky on your monitor reminding you that the password is Jen and the password is still safe.