I have heard lots of "methods" for finding your calling. I don't know if God follows our methods, though. Some say you have to get out of your head and look into your heart. I'm not altogether sure how to do that, but I have heard some ideas that I think could prove helpful.
Most of us have a tendency to look at what presents itself and think that fate or destiny chooses us and we just go with the path of least resistance. We might put a little more effort in it and actually take some personality and aptitude tests to help us decide.
But the Bible says, "Delight yourself in the Lord, and He will give you the desires of your heart." When I looked up the word "delight" I found something interesting. It means "to be molded and shaped by."
So in reading the Bible and praying and communing with the Spirit of God, do not seek what you can do for Him, or even what He can do for you, but just to be with Him, to know Him. He is the I AM, and He also wants us to BE before we do.
From that place of peace and surrender and of just being instead of doing, our hearts become still and we gain clarity of vision and desire that is from that pure place.
Your calling is the thing you would do if all restraints were taken off. If you had all the time, all the money, and all the resources in the world at your disposal, if you were told that you cannot fail, no matter what, what would you do with your life?
If you think about it, God has no limits, in money, time, or resources, He can establish you. When you are fulfilling that calling, is it not reasonable to believe He will provide you with everything you need to do what He is calling you to do?
We let fear stop us from following our God-given destiny only when we don't believe He can and will carry us to the finish line as He promised.
What makes you cry? What makes you angry? What do you love so much, what are you so passionate about, that you would gladly do it for nothing? That is your calling. It's not written on a banner across the sky, it is written in the quiet recesses of your heart.