Once you sign up for a free ERC20 wallet (like My Ether Wallet), you can start participating in airdrops forms using your public address.

Then all you have to do is find some

AIRDROPS THAT MAYBE DON'T SUCK

https://docs.google.com/spreadsheets/d/1OoNKjUxXkp-g0Etn5XZdD8lD3FiUngY8GfDNNoAWGPc

Like this one.

https://gonetwork.co/airdrop

Winners of ETHWaterloo - the world's largest Ethereum hackathon. I bet you didn't know about that.

Check out the Google spreadsheet for an active, ongoing list of other airdrops that maybe don't suck. I update it daily.