1. Don't run before you are sent. Moses ran ahead of God before he was sent. I see students doing this all the time. They just can't wait to "get into ministry." But God is saying, "I haven't sent you -- yet. I've got to prepare you first."
2. Don't retreat when you fail. Frankly, I had to deal with this when I was a student at Biola. I dropped out of my beginning Greek class after only 3 weeks. I felt defeated. Useless. Inferior. But I had forgotten something. All God asks is that we are available, in fact, broken. That's when I prayed, "God, I'm yours. Weaknesses and all. Just use me anywhere you like." Two years later I was teaching Greek at Biola.
Let me repeat that. A struggling start doesn't necessitate a limited life. When it's God who blesses a life, there's no room for defeat.