I've joined the airdrop over the past 3 months and I only get very little value from the airdrop, the majority of which I have to keep it to add value.
So how can I earn a few hundred dollars a month if the bounty is a good plan?

As a fan of airdrop, of course, you have pocketed many tricks to collect coins. So for this, don't let you become a spammer, try to manage well the airdrop that you follow to achieve the value you want.