To maximize earnings in L2 network airdrops on Optimism and Arbitrum, first, stay updated on the latest news and announcements from these networks. Participate actively in their testnets and early - stage projects. This not only increases your chances of being eligible for airdrops but also helps you understand the network's features better. Build a diversified portfolio of wallets within these networks to increase your exposure. Also, engage with the community through forums and social media to stay informed about potential airdrop opportunities and requirements.