Answer:
Girls like confidence because if you're comfortable with yourself then she can be comfortable with you. Your confidence lowers her guard and she'll want to be close to you. That doesn't mean be someone you're not. Don't move around a lot it makes you look uncomfortable. Hold a steady pose, relaxed not stiff. Maintain eye contact while in conversation and try not to stutter. This might sound corny but as you converse, gaze into her eyes while you give her a smile occasionally and think to yourself always how awesome you are and how bad she must want you. This thinking will improve confidence over time and will eventually manifest itself into truth. Never fear rejection because practice makes perfect.