Provoking title, insightful research:
TL;DR: How to Buy Happiness with Money
Not enough; want to read more: Prosocial Spending and Happiness: Using Money to Benefit Others Pays Off
If money doesn't make you happy, then you probably aren't spending it right
Journal of Consumer Psychology 21 (2011) 115–125
The relationship between money and happiness is surprisingly weak, which may stem in part from the way people spend it. Drawing on empirical research, we propose eight principles designed to help consumers get more happiness for their money. Specifically, we suggest that consumers should (1) buy more experiences and fewer material goods; (2) use their money to benefit others rather than themselves; (3) buy many small pleasures rather than fewer large ones; (4) eschew extended warranties and other forms of overpriced insurance; (5) delay consumption; (6) consider how peripheral features of their purchases may affect their day-to-day lives; (7) beware of comparison shopping; and (8) pay close attention to the happiness of others.
TL;DR: How to Buy Happiness with Money
Not enough; want to read more: Prosocial Spending and Happiness: Using Money to Benefit Others Pays Off