Tā kàn dào biérén zhèyàng zhuànqián, yě xiǎng rúfǎpáozhì.
Seeing others make money that way, he wanted to follow the same recipe.
Tips
history
From the Qing novel 《镜花缘》 by Li Ruzhen: "即如法炮制,果然把阵破了" — they carried out the method and indeed broke the formation. 炮制 (páozhì) is the traditional Chinese-medicine term for processing herbs by roasting — hence "follow the recipe as prescribed."
mistakes
炮 here reads páo, not pào. It refers to medicinal roasting/processing, not cannons. A very common mistake among native speakers too.