1. Challenge Your Strength. Falling into a comfort zone can be one of your biggest enemies in the gym. Your biceps grow larger only when you make demands on them above what their accustomed to.
2. Understand Your Anatomy. Account for each muscle. Training and accounting for the long head, short head, brachialis, brachioradialis, etc. will help produce the greatest overall strength and size gains.
3. Isolate the Muscle. Consider adding movements that isolate the muscle. Preacher curls, concentration curls, etc. will help eliminate your ability to use momentum