5. Do a good deed
As much as we might like to think that we do nice things for others solely for their benefit, there may be a secret underlying reason that goes a bit beyond that. Doing nice things for others has been shown to increase positive feelings for those who do the deeds in addition to those that they are intended to benefit. Volunteering is a great way to help others and make yourself happier, but there is a host of simpler things you can do for others that may be just as beneficial, such as helping someone load groceries in their car, cleaning the kitchen for your significant other or offering your seat to someone on the bus.