Point 1(Do not shut down someone's idea)
Sometimes due to overconfidence in your own idea, you might reject any other ideas. Try to listen to your team mates, maybe their ideas are better.
Point 2(Be a team player)
Do not just sit down there and listen to your team member's idea, contribute something, share your opinion.
Point 3(Choose the right people)
Choose the people that are aiming for the same goals.