We do have different ways or earning bitcoin depending on where we are good at. In my case I receive BTC as payment for work which is posting or simply as a bounty hunter. I tried investing before but it didn't work for me as well as trading. I lose a lot in trading although I am trying it again with an amount I can afford to lose and to coins that I know I can hold for a long time. Airdrops? I am not really sure about this due to lot of scams before but I'm trying to get back my trust on airdrops. I just made myself more careful to airdrops that I am going to participate.