simple, don't be afraid, and don't be desperate, go simple, show your simple attitude and just focus on your education, if you are fully funded and  you don't need any money from nepal, then don't show any document about financial, one of my friend just walked with his I-20 and his degree got visa in 2 min with congratulation, he was in the same situation (fully funded). Remember don't mention any kind of financial goal, focus on intellectual only.