Hang out with the people you're already buddies with. Make it reciprocal, don't always be the one inviting the other, they should invite you half the time. If y

Hang out with the people you're already buddies with. Make it reciprocal, don't always be the one inviting the other, they should invite you half the time. If you foster an environment where you already have a collegiate environment at work, your subordinates will naturally like to move that fun out of the office from time to time. In short, make it optional, don't make it regular ("we have a happy hour every Friday :^D"), and make sure it's reciprocal.