Reciprocity (“People tend to return a favor.”), Commitment (“If people commit…they are more likely to honor that commitment.”), Social Proof (“People will do things they see other people are doing.”), Authority (“People will tend to obey authority figures.”), Liking (“People are easily persuaded by other people they like.”), and Scarcity (“Perceived scarcity will generate demand”). (related: foot-in-the-door technique)
Source:
Gabriel Weinberg’s Mental Models I Find Repeatedly Useful