This is very difficult to answer sometimes. But, merely asking the question says something. It says that you want to do God’s will. Discerning may be the difficult part, but just wanting to know what God wants of you is a positive step. Many figure they are doing God’s will, but never actually ask Him.
Beyond asking the question, we often feel that we are not getting an answer. The answer can be found in many ways. First is always the primary vocation that you are given. If you are not living out your primary vocation, why would God ask for you to do anything else? It would be like asking the plumber to look at your broken wrist when he has not even fixed the leak you hired him to fix.
Second, do you spend time in silence asking this question? “Then the LORD said: Go out and stand on the mountain before the LORD; the LORD will pass by. There was a strong and violent wind rending the mountains and crushing rocks before the LORD—but the LORD was not in the wind; after the wind, an earthquake—but the LORD was not in the earthquake; after the earthquake, fire—but the LORD was not in the fire; after the fire, a light silent sound. When he heard this, Elijah hid his face in his cloak” – [1 Kings 19:11-13]
If you are hoping for neon lights, you are not looking. You are expecting God to make it completely obvious regardless without need for looking. Noticing neon lights does not take any effort for searching on our part. God is looking for us to make an effort. There, God knows that you are serious about doing His Will. Why would He want you to know His will for you, if you were not serious about doing it?