The Playbook is a book authored by Barney Stinson that contains a collection of scams Barney uses for picking up women.
The SNASA
Barney goes up to a girl and claims he works for a secret government agency called “SNASA”, or “Secret NASA”, and claims to have been to the identically-named “SMoon”.
The Cheap Trick
Barney claims that he is the bass player of a rock band with the ironic name of “Cheap Trick” (a real-life band).
The My Penis Grants Wishes
Dressed as a genie, Barney claims that his penis, like a magic lamp, grants wishes if one rubs it hard enough.
The He’s Not Coming
Barney goes to the observation deck of the Empire State Building (a rather romantic setting) and tells random women “He’s not coming” until one breaks down in his arms with the realization that their boyfriend isn’t coming for whatever reason.
The Don’t Drink That
Barney stops a girl from drinking a drink, and then claims that Ted slipped something in there, resulting in Ted getting tackled by the bartender.
The Ted Mosby
Dressed like Ted, Barney says he was left at the altar.
The Mrs. Stinsfire
Barney poses as a maid at a school in order to see girls in the bathroom. This is a tribute to the film, Mrs. Doubtfire.
The Lorenzo Von Matterhorn
Barney creates several fake websites that make him look like an extremely famous and noble person named Lorenzo Von Matterhorn, then tricks a girl into seeing the sites and become interested in him.
The Scuba Diver
(page 136; the last page, which was torn out of the book as part of the elaborate plot): Entire process is the episode The Playbook.
If you wanna know how the plays are done, you have this video explaining every scam above, and some more!
How I Met Your Mother 