Imagine reaching and touching a tree or building that is a long distance away. Maintain this feeling, and have your friend try to bend your arm again. Ki Tricks, you and your friends should really try to help each other out. You need to try to help each other catch the right feeling. So don't try to bend each other's arms with all your might - at least initially.
Different visualizations work better for different people.
Try thinking of your arm as a fire hose, and water shooting out of it. Or, think of yourself as being extremely thirsty and reaching all the way across the room for a cold drink. Or, just extend your arm and keep One-Point. Don't make your arm completely straight. Put a slight bend in your elbow.