Playing offense means testing your ideas against others. You don’t resist change and don’t fear being wrong. That’s playing defense. Instead you actively look for ways to improve your idea.
You can find flaws in your reasoning or consider your idea in light of new information you were unaware of. You can also find support for ideas and add additional content to it. Additionally, you can abandon your idea if you find that it no longer serves you and focus on another one.
Regardless of what you find, your idea will become more nuanced. It will become a stronger and better idea overall.
If you want to play offense, actively look for opposing ideas. Read books, watch lectures or listen to podcasts with the goal of understanding the content you consume. Apply what you learn to your idea and look for ways to improve it. Take notes, draw mindmaps or highlight a lot. Add valuable or subtract wrong information.
Thus, by playing offense you’ll gain a significant advantage over playing defense. You will grow your ideas, improve your reasoning and improve your thinking rapidly.