Final answer:
The quickest and most effective way to change an attitude is to develop a growth mindset, reflect on successful individuals, embrace cognitive dissonance, and focus on changing one's outlook.
Step-by-step explanation:
The quickest and most effective way to change an attitude is to develop a growth mindset, which involves being open to learning, having a positive outlook, and being adaptable. Reflect on successful individuals and model their approach. Additionally, cognitive dissonance, which is the discomfort caused by holding contradictory beliefs, can motivate us to change our attitudes. Lastly, changing our circumstances may not always be possible, but focusing on changing our outlook can lead to attitude change.