Part of the practice of true and perfect joy is to share it with others:

I have said these things to you so that my joy may be in you, and that your joy may be complete. (John 15:11)

Sharing our happiness with others only increases our own happiness and brings joy to others. The Beatitudes (Matthew 5:3-11) offers me vital wisdom when it comes to sharing joy with others:

Blessed are the poor in spirit. I must not be governed by a mindset of scarcity, thinking of joy as some sort of commodity that I lose if I share it with others. On the contrary, joy is only increased when I share it with others.
Blessed are those who mourn. I can never force joy and happiness can on another person. If I am going to share my joy, I have to be willing to understand that my gift may not be well received at the time I share it.
Blessed are the meek. I should never be afraid to share my happiness and joy, even in times I will be derided as being naive or ridiculed as a Pollyanna.
Blessed are those who hunger and thirst for righteousness. I need to remember that people have a right to dignity; happiness and joy is a part of what it means to be human. A person cannot have dignity with knowing joy.
Blessed are the merciful. Sharing joy is an act of mercy; not sharing joy is an act of cruelty, to myself and to others.
Blessed are the pure of heart. Happiness cannot be manufactured, that is, it needs to remain simple. The joys that bring the most happiness to others are the simple joys all people can relate to.
Blessed are the peacemakers. When I share joy, I recognize another person's inherent need and right to be happy. On this assumption of equality, we can begin to build a bridge of understanding and peace.
Blessed are those who are persecuted for righteousness’ sake. When another person shares his or her joy with me, I am often tempted with feelings of envy or bitterness. "Why should they receive such good fortune?" I ask myself as I immediately judge them as not being worthy of it. These are the persecutions that will prevent me from receiving the gift of another person's joy, thus preventing my own.
Blessed are you when people revile you and persecute you and utter all kinds of evil against you falsely on my account. Sharing my joy with another person--and sharing in their joy as well--is an act of love. "In love," wrote St. Ignatius of Loyola, "one always wants to give to the other what one has." If I am going to love another as myself, then I will want to share my joy with them so that they will be happy.

To be a person of joy doesn't just mean that I am happy and joyful. To be a person of joy means that I want to share my joy and happiness with others, and receive their joy and happiness as well. Perhaps that is how we can define our vocation: it is the manner in which we share our joy and happiness with others.

Using that definition, what is your vocation?