Qualifications
The list of things you need to become a missionary is a little fuzzy and full of big concepts like "a distinct calling from God." We're not sure how to define that, but we are pretty sure it’s something each person needs to judge for themselves. And we know that whatever it is you feel, you should be relatively certain of your purpose as a missionary.
Apart from your personal relationship with your God, here are some other qualifications of effective foreign missionaries that are slightly more in our realm of expertise. You'll need to be an effective orator. You need to get along with a lot of people. A lot. You need to be able to stick to a budget, and you should be patient and perseverant.
Because those aren't enough qualifications, here's a couple more. Demonstrate a deep commitment to your church and be in line with their vision for the world. Maybe you're a pastor. Maybe you teach a Sunday school class. And if you can, go on one of their shorter mission trips to feel out whether you could do this in the long-term.
At the end of the day, religious organizations often like college graduates for their missionaries, especially ones well-versed in theology. And you're in an even better position if you can pick up a useful trade or skill along the way. The ultimate missionary? A brick-laying, woodworking carpenter and theologian with a decade's experience as a pastor. So easy, we know.