Zarrella's Hierarchy of Contagiousness: The Science, Design, and Engineering of Contagious Ideas

The person must be exposed to your content. This means that the person has to be following you on Twitter, be a fan of your page on Facebook, subscribe to your email list, and so on. The person must become aware of your specific piece of content (the idea you want to spread). He has to read your tweet or open your email message. The person must be

Memory isn’t a big problem anymore. You have to be able only to copy and paste a link, not remember an entire epic poem. The change in the environment has introduced a different selection pressure into the mental landscape: attention. There are now so many ideas floating around the Web, they fight for simple awareness.

you should not be afraid to identify yourself authoritatively. Tell people why they should listen to you. In that same study, I found that Twitter users with the confidence to use words like “official,” “founder,” “author,” and “expert” to describe themselves also had more followers than the average. Don’t feel limited to using the term “guru.”

When I asked people why they share ideas with their friends, they consistently told me that they wanted to build a reputation as a thought leader. This would ensure that people would share valuable scarce information reciprocally with them. It’s not about altruism, then; it’s about reciprocity.

Fill knowledge gaps with your ideas.

If your ideas reinforce my reputation, I’ll share them.

Imitators follow optimizers around and learn from their mistakes.

the AIDA concept. It represents the steps in a purchasing decision: Attention, Interest, Desire, and Action. The attention of the customer must be attracted, interest must be raised, desire must be established, and finally, the act of purchasing must be completed.

Structure ideas to both arouse attention and stick to memory. Take old content and put it in a new format, or put new content into an old format.