Tell me how to join airdrip, do I need to register or something in this spirit?
You get free OMGs if you had min. 0,1 ETH on Jul-07-2017, but only very, very few (some guy here made a calculation that came out on one milli-OMG for each ETH).
You don't have to register, you just need a wallet that can handle ERC20-token like MEW (myetherwallet). If you held some ETHs in July - Snapshot was taken at
block 3988888 - then they automatically show up in that wallet.
Updates on the airdrop:
update 1update 2update 3